diff --git a/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/AbstractTwoUsersOmemoIntegrationTest.java b/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/AbstractTwoUsersOmemoIntegrationTest.java
index 4903fe72b..68cd5f30c 100644
--- a/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/AbstractTwoUsersOmemoIntegrationTest.java
+++ b/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/AbstractTwoUsersOmemoIntegrationTest.java
@@ -19,6 +19,7 @@ package org.jivesoftware.smackx.omemo;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 
+import java.io.IOException;
 import java.util.logging.Level;
 
 import org.jivesoftware.smack.SmackException;
@@ -64,7 +65,7 @@ public abstract class AbstractTwoUsersOmemoIntegrationTest extends AbstractOmemo
     }
 
     @AfterClass
-    public void cleanUp() {
+    public void cleanUp() throws IOException {
         alice.stopStanzaAndPEPListeners();
         bob.stopStanzaAndPEPListeners();
         OmemoManagerSetupHelper.cleanUpPubSub(alice);
diff --git a/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/OmemoMamDecryptionTest.java b/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/OmemoMamDecryptionTest.java
index 2c3017e74..b562db8f8 100644
--- a/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/OmemoMamDecryptionTest.java
+++ b/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/OmemoMamDecryptionTest.java
@@ -18,6 +18,7 @@ package org.jivesoftware.smackx.omemo;
 
 import static org.junit.Assert.assertEquals;
 
+import java.io.IOException;
 import java.util.List;
 
 import org.jivesoftware.smack.SmackException;
@@ -50,7 +51,7 @@ public class OmemoMamDecryptionTest extends AbstractTwoUsersOmemoIntegrationTest
     @SmackIntegrationTest
     public void mamDecryptionTest() throws XMPPException.XMPPErrorException, SmackException.NotLoggedInException,
             SmackException.NotConnectedException, InterruptedException, SmackException.NoResponseException,
-            CryptoFailedException, UndecidedOmemoIdentityException {
+            CryptoFailedException, UndecidedOmemoIdentityException, IOException {
         // Make sure, Bobs server stores messages in the archive
         MamManager bobsMamManager = MamManager.getInstanceFor(bob.getConnection());
         bobsMamManager.enableMamForAllMessages();
diff --git a/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/OmemoManagerSetupHelper.java b/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/OmemoManagerSetupHelper.java
index 83234924d..97fa93820 100644
--- a/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/OmemoManagerSetupHelper.java
+++ b/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/OmemoManagerSetupHelper.java
@@ -20,6 +20,7 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
+import java.io.IOException;
 import java.util.HashMap;
 
 import org.jivesoftware.smack.SmackException;
@@ -46,7 +47,7 @@ public class OmemoManagerSetupHelper {
     public static void trustAllIdentities(OmemoManager alice, OmemoManager bob)
             throws InterruptedException, SmackException.NotConnectedException, SmackException.NotLoggedInException,
             SmackException.NoResponseException, CannotEstablishOmemoSessionException, CorruptedOmemoKeyException,
-            XMPPException.XMPPErrorException, PubSubException.NotALeafNodeException {
+            XMPPException.XMPPErrorException, PubSubException.NotALeafNodeException, IOException {
         Roster roster = Roster.getInstanceFor(alice.getConnection());
 
         if (alice.getOwnJid() != bob.getOwnJid() &&
@@ -66,7 +67,7 @@ public class OmemoManagerSetupHelper {
     public static void trustAllIdentitiesWithTests(OmemoManager alice, OmemoManager bob)
             throws InterruptedException, SmackException.NotConnectedException, SmackException.NotLoggedInException,
             SmackException.NoResponseException, CannotEstablishOmemoSessionException, CorruptedOmemoKeyException,
-            XMPPException.XMPPErrorException, PubSubException.NotALeafNodeException {
+            XMPPException.XMPPErrorException, PubSubException.NotALeafNodeException, IOException {
         alice.requestDeviceListUpdateFor(bob.getOwnJid());
         HashMap<OmemoDevice, OmemoFingerprint> fps1 = alice.getActiveFingerprints(bob.getOwnJid());
 
@@ -124,7 +125,7 @@ public class OmemoManagerSetupHelper {
         }
     }
 
-    public static void cleanUpPubSub(OmemoManager omemoManager) {
+    public static void cleanUpPubSub(OmemoManager omemoManager) throws IOException {
         PubSubManager pm = PubSubManager.getInstanceFor(omemoManager.getConnection(), omemoManager.getOwnJid());
         try {
             omemoManager.requestDeviceListUpdateFor(omemoManager.getOwnJid());
diff --git a/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/ReadOnlyDeviceIntegrationTest.java b/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/ReadOnlyDeviceIntegrationTest.java
index 3164d6668..815d4a032 100644
--- a/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/ReadOnlyDeviceIntegrationTest.java
+++ b/smack-integration-test/src/main/java/org/jivesoftware/smackx/omemo/ReadOnlyDeviceIntegrationTest.java
@@ -20,6 +20,8 @@ import static junit.framework.TestCase.assertEquals;
 import static junit.framework.TestCase.assertFalse;
 import static junit.framework.TestCase.assertTrue;
 
+import java.io.IOException;
+
 import org.jivesoftware.smack.SmackException;
 import org.jivesoftware.smack.XMPPException;
 import org.jivesoftware.smackx.omemo.exceptions.CryptoFailedException;
@@ -37,7 +39,9 @@ public class ReadOnlyDeviceIntegrationTest extends AbstractTwoUsersOmemoIntegrat
     }
 
     @SmackIntegrationTest
-    public void test() throws InterruptedException, SmackException.NoResponseException, SmackException.NotLoggedInException, SmackException.NotConnectedException, CryptoFailedException, UndecidedOmemoIdentityException {
+    public void test() throws InterruptedException, SmackException.NoResponseException,
+                    SmackException.NotLoggedInException, SmackException.NotConnectedException, CryptoFailedException,
+                    UndecidedOmemoIdentityException, IOException {
         boolean prevIgnoreReadOnlyConf = OmemoConfiguration.getIgnoreReadOnlyDevices();
         int prevMaxMessageCounter = OmemoConfiguration.getMaxReadOnlyMessageCount();
 
diff --git a/smack-omemo-signal/src/main/java/org/jivesoftware/smackx/omemo/signal/SignalOmemoRatchet.java b/smack-omemo-signal/src/main/java/org/jivesoftware/smackx/omemo/signal/SignalOmemoRatchet.java
index de20f69a9..c219b6f14 100644
--- a/smack-omemo-signal/src/main/java/org/jivesoftware/smackx/omemo/signal/SignalOmemoRatchet.java
+++ b/smack-omemo-signal/src/main/java/org/jivesoftware/smackx/omemo/signal/SignalOmemoRatchet.java
@@ -20,6 +20,7 @@
  */
 package org.jivesoftware.smackx.omemo.signal;
 
+import java.io.IOException;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
@@ -73,7 +74,7 @@ public class SignalOmemoRatchet
     @Override
     public byte[] doubleRatchetDecrypt(OmemoDevice sender, byte[] encryptedKey)
             throws CorruptedOmemoKeyException, NoRawSessionException, CryptoFailedException,
-            UntrustedOmemoIdentityException {
+            UntrustedOmemoIdentityException, IOException {
 
         SessionCipher cipher = getCipher(sender);
         byte[] decryptedKey;
diff --git a/smack-omemo-signal/src/main/java/org/jivesoftware/smackx/omemo/signal/SignalOmemoStoreConnector.java b/smack-omemo-signal/src/main/java/org/jivesoftware/smackx/omemo/signal/SignalOmemoStoreConnector.java
index 0f607603a..1aae64856 100644
--- a/smack-omemo-signal/src/main/java/org/jivesoftware/smackx/omemo/signal/SignalOmemoStoreConnector.java
+++ b/smack-omemo-signal/src/main/java/org/jivesoftware/smackx/omemo/signal/SignalOmemoStoreConnector.java
@@ -20,6 +20,7 @@
  */
 package org.jivesoftware.smackx.omemo.signal;
 
+import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.TreeMap;
@@ -79,7 +80,7 @@ public class SignalOmemoStoreConnector
     public IdentityKeyPair getIdentityKeyPair() {
         try {
             return omemoStore.loadOmemoIdentityKeyPair(getOurDevice());
-        } catch (CorruptedOmemoKeyException e) {
+        } catch (CorruptedOmemoKeyException | IOException e) {
             LOGGER.log(Level.SEVERE, "IdentityKeyPair seems to be invalid.", e);
             return null;
         }
@@ -103,7 +104,11 @@ public class SignalOmemoStoreConnector
             throw new AssertionError(e);
         }
 
-        omemoStore.storeOmemoIdentityKey(getOurDevice(), device, identityKey);
+        try {
+            omemoStore.storeOmemoIdentityKey(getOurDevice(), device, identityKey);
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
         return true;
     }
 
@@ -118,7 +123,12 @@ public class SignalOmemoStoreConnector
 
     @Override
     public PreKeyRecord loadPreKey(int i) throws InvalidKeyIdException {
-        PreKeyRecord preKey = omemoStore.loadOmemoPreKey(getOurDevice(), i);
+        PreKeyRecord preKey;
+        try {
+            preKey = omemoStore.loadOmemoPreKey(getOurDevice(), i);
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
 
         if (preKey == null) {
             throw new InvalidKeyIdException("No PreKey with Id " + i + " found.");
@@ -129,7 +139,11 @@ public class SignalOmemoStoreConnector
 
     @Override
     public void storePreKey(int i, PreKeyRecord preKeyRecord) {
-        omemoStore.storeOmemoPreKey(getOurDevice(), i, preKeyRecord);
+        try {
+            omemoStore.storeOmemoPreKey(getOurDevice(), i, preKeyRecord);
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
     }
 
     @Override
@@ -155,7 +169,12 @@ public class SignalOmemoStoreConnector
             throw new AssertionError(e);
         }
 
-        SessionRecord record = omemoStore.loadRawSession(getOurDevice(), device);
+        SessionRecord record;
+        try {
+            record = omemoStore.loadRawSession(getOurDevice(), device);
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
 
         if (record != null) {
             return record;
@@ -173,7 +192,11 @@ public class SignalOmemoStoreConnector
             throw new AssertionError(e);
         }
 
-        return new ArrayList<>(omemoStore.loadAllRawSessionsOf(getOurDevice(), jid).keySet());
+        try {
+            return new ArrayList<>(omemoStore.loadAllRawSessionsOf(getOurDevice(), jid).keySet());
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
     }
 
     @Override
@@ -185,7 +208,11 @@ public class SignalOmemoStoreConnector
             throw new AssertionError(e);
         }
 
-        omemoStore.storeRawSession(getOurDevice(), device, sessionRecord);
+        try {
+            omemoStore.storeRawSession(getOurDevice(), device, sessionRecord);
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
     }
 
     @Override
@@ -226,7 +253,12 @@ public class SignalOmemoStoreConnector
 
     @Override
     public SignedPreKeyRecord loadSignedPreKey(int i) throws InvalidKeyIdException {
-        SignedPreKeyRecord signedPreKeyRecord = omemoStore.loadOmemoSignedPreKey(getOurDevice(), i);
+        SignedPreKeyRecord signedPreKeyRecord;
+        try {
+            signedPreKeyRecord = omemoStore.loadOmemoSignedPreKey(getOurDevice(), i);
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
         if (signedPreKeyRecord == null) {
             throw new InvalidKeyIdException("No signed preKey with id " + i + " found.");
         }
@@ -236,14 +268,22 @@ public class SignalOmemoStoreConnector
     @Override
     public List<SignedPreKeyRecord> loadSignedPreKeys() {
 
-        TreeMap<Integer, SignedPreKeyRecord> signedPreKeyRecordHashMap =
-                omemoStore.loadOmemoSignedPreKeys(getOurDevice());
+        TreeMap<Integer, SignedPreKeyRecord> signedPreKeyRecordHashMap;
+        try {
+            signedPreKeyRecordHashMap = omemoStore.loadOmemoSignedPreKeys(getOurDevice());
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
         return new ArrayList<>(signedPreKeyRecordHashMap.values());
     }
 
     @Override
     public void storeSignedPreKey(int i, SignedPreKeyRecord signedPreKeyRecord) {
-        omemoStore.storeOmemoSignedPreKey(getOurDevice(), i, signedPreKeyRecord);
+        try {
+            omemoStore.storeOmemoSignedPreKey(getOurDevice(), i, signedPreKeyRecord);
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
     }
 
     @Override
diff --git a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/CachingOmemoStore.java b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/CachingOmemoStore.java
index 7ab0bcde6..d83984e6c 100644
--- a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/CachingOmemoStore.java
+++ b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/CachingOmemoStore.java
@@ -16,6 +16,7 @@
  */
 package org.jivesoftware.smackx.omemo;
 
+import java.io.IOException;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.SortedSet;
@@ -80,7 +81,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
 
     @Override
     public T_IdKeyPair loadOmemoIdentityKeyPair(OmemoDevice userDevice)
-            throws CorruptedOmemoKeyException {
+            throws CorruptedOmemoKeyException, IOException {
         T_IdKeyPair pair = getCache(userDevice).identityKeyPair;
 
         if (pair == null && persistent != null) {
@@ -94,7 +95,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public void storeOmemoIdentityKeyPair(OmemoDevice userDevice, T_IdKeyPair identityKeyPair) {
+    public void storeOmemoIdentityKeyPair(OmemoDevice userDevice, T_IdKeyPair identityKeyPair) throws IOException {
         getCache(userDevice).identityKeyPair = identityKeyPair;
         if (persistent != null) {
             persistent.storeOmemoIdentityKeyPair(userDevice, identityKeyPair);
@@ -111,7 +112,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
 
     @Override
     public T_IdKey loadOmemoIdentityKey(OmemoDevice userDevice, OmemoDevice contactsDevice)
-            throws CorruptedOmemoKeyException {
+            throws CorruptedOmemoKeyException, IOException {
         T_IdKey idKey = getCache(userDevice).identityKeys.get(contactsDevice);
 
         if (idKey == null && persistent != null) {
@@ -125,7 +126,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public void storeOmemoIdentityKey(OmemoDevice userDevice, OmemoDevice device, T_IdKey t_idKey) {
+    public void storeOmemoIdentityKey(OmemoDevice userDevice, OmemoDevice device, T_IdKey t_idKey) throws IOException {
         getCache(userDevice).identityKeys.put(device, t_idKey);
         if (persistent != null) {
             persistent.storeOmemoIdentityKey(userDevice, device, t_idKey);
@@ -141,7 +142,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public void storeOmemoMessageCounter(OmemoDevice userDevice, OmemoDevice contactsDevice, int counter) {
+    public void storeOmemoMessageCounter(OmemoDevice userDevice, OmemoDevice contactsDevice, int counter) throws IOException {
         getCache(userDevice).messageCounters.put(contactsDevice, counter);
         if (persistent != null) {
             persistent.storeOmemoMessageCounter(userDevice, contactsDevice, counter);
@@ -149,7 +150,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public int loadOmemoMessageCounter(OmemoDevice userDevice, OmemoDevice contactsDevice) {
+    public int loadOmemoMessageCounter(OmemoDevice userDevice, OmemoDevice contactsDevice) throws IOException {
         Integer counter = getCache(userDevice).messageCounters.get(contactsDevice);
         if (counter == null && persistent != null) {
             counter = persistent.loadOmemoMessageCounter(userDevice, contactsDevice);
@@ -165,7 +166,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public void setDateOfLastReceivedMessage(OmemoDevice userDevice, OmemoDevice from, Date date) {
+    public void setDateOfLastReceivedMessage(OmemoDevice userDevice, OmemoDevice from, Date date) throws IOException {
         getCache(userDevice).lastMessagesDates.put(from, date);
         if (persistent != null) {
             persistent.setDateOfLastReceivedMessage(userDevice, from, date);
@@ -173,7 +174,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public Date getDateOfLastReceivedMessage(OmemoDevice userDevice, OmemoDevice from) {
+    public Date getDateOfLastReceivedMessage(OmemoDevice userDevice, OmemoDevice from) throws IOException {
         Date last = getCache(userDevice).lastMessagesDates.get(from);
 
         if (last == null && persistent != null) {
@@ -187,7 +188,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public void setDateOfLastDeviceIdPublication(OmemoDevice userDevice, OmemoDevice contactsDevice, Date date) {
+    public void setDateOfLastDeviceIdPublication(OmemoDevice userDevice, OmemoDevice contactsDevice, Date date) throws IOException {
         getCache(userDevice).lastDeviceIdPublicationDates.put(contactsDevice, date);
         if (persistent != null) {
             persistent.setDateOfLastReceivedMessage(userDevice, contactsDevice, date);
@@ -195,7 +196,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public Date getDateOfLastDeviceIdPublication(OmemoDevice userDevice, OmemoDevice contactsDevice) {
+    public Date getDateOfLastDeviceIdPublication(OmemoDevice userDevice, OmemoDevice contactsDevice) throws IOException {
         Date last = getCache(userDevice).lastDeviceIdPublicationDates.get(contactsDevice);
 
         if (last == null && persistent != null) {
@@ -209,7 +210,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public void setDateOfLastSignedPreKeyRenewal(OmemoDevice userDevice, Date date) {
+    public void setDateOfLastSignedPreKeyRenewal(OmemoDevice userDevice, Date date) throws IOException {
         getCache(userDevice).lastRenewalDate = date;
         if (persistent != null) {
             persistent.setDateOfLastSignedPreKeyRenewal(userDevice, date);
@@ -217,7 +218,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public Date getDateOfLastSignedPreKeyRenewal(OmemoDevice userDevice) {
+    public Date getDateOfLastSignedPreKeyRenewal(OmemoDevice userDevice) throws IOException {
         Date lastRenewal = getCache(userDevice).lastRenewalDate;
 
         if (lastRenewal == null && persistent != null) {
@@ -231,7 +232,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public T_PreKey loadOmemoPreKey(OmemoDevice userDevice, int preKeyId) {
+    public T_PreKey loadOmemoPreKey(OmemoDevice userDevice, int preKeyId) throws IOException {
         T_PreKey preKey = getCache(userDevice).preKeys.get(preKeyId);
 
         if (preKey == null && persistent != null) {
@@ -245,7 +246,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public void storeOmemoPreKey(OmemoDevice userDevice, int preKeyId, T_PreKey t_preKey) {
+    public void storeOmemoPreKey(OmemoDevice userDevice, int preKeyId, T_PreKey t_preKey) throws IOException {
         getCache(userDevice).preKeys.put(preKeyId, t_preKey);
         if (persistent != null) {
             persistent.storeOmemoPreKey(userDevice, preKeyId, t_preKey);
@@ -261,7 +262,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public TreeMap<Integer, T_PreKey> loadOmemoPreKeys(OmemoDevice userDevice) {
+    public TreeMap<Integer, T_PreKey> loadOmemoPreKeys(OmemoDevice userDevice) throws IOException {
         TreeMap<Integer, T_PreKey> preKeys = getCache(userDevice).preKeys;
 
         if (preKeys.isEmpty() && persistent != null) {
@@ -272,7 +273,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public T_SigPreKey loadOmemoSignedPreKey(OmemoDevice userDevice, int signedPreKeyId) {
+    public T_SigPreKey loadOmemoSignedPreKey(OmemoDevice userDevice, int signedPreKeyId) throws IOException {
         T_SigPreKey sigPreKey = getCache(userDevice).signedPreKeys.get(signedPreKeyId);
 
         if (sigPreKey == null && persistent != null) {
@@ -286,7 +287,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public TreeMap<Integer, T_SigPreKey> loadOmemoSignedPreKeys(OmemoDevice userDevice) {
+    public TreeMap<Integer, T_SigPreKey> loadOmemoSignedPreKeys(OmemoDevice userDevice) throws IOException {
         TreeMap<Integer, T_SigPreKey> sigPreKeys = getCache(userDevice).signedPreKeys;
 
         if (sigPreKeys.isEmpty() && persistent != null) {
@@ -299,7 +300,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     @Override
     public void storeOmemoSignedPreKey(OmemoDevice userDevice,
                                        int signedPreKeyId,
-                                       T_SigPreKey signedPreKey) {
+                                       T_SigPreKey signedPreKey) throws IOException {
         getCache(userDevice).signedPreKeys.put(signedPreKeyId, signedPreKey);
         if (persistent != null) {
             persistent.storeOmemoSignedPreKey(userDevice, signedPreKeyId, signedPreKey);
@@ -315,7 +316,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public T_Sess loadRawSession(OmemoDevice userDevice, OmemoDevice contactsDevice) {
+    public T_Sess loadRawSession(OmemoDevice userDevice, OmemoDevice contactsDevice) throws IOException {
         HashMap<Integer, T_Sess> contactSessions = getCache(userDevice).sessions.get(contactsDevice.getJid());
         if (contactSessions == null) {
             contactSessions = new HashMap<>();
@@ -334,7 +335,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public HashMap<Integer, T_Sess> loadAllRawSessionsOf(OmemoDevice userDevice, BareJid contact) {
+    public HashMap<Integer, T_Sess> loadAllRawSessionsOf(OmemoDevice userDevice, BareJid contact) throws IOException {
         HashMap<Integer, T_Sess> sessions = getCache(userDevice).sessions.get(contact);
         if (sessions == null) {
             sessions = new HashMap<>();
@@ -349,7 +350,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public void storeRawSession(OmemoDevice userDevice, OmemoDevice contactsDevicece, T_Sess session) {
+    public void storeRawSession(OmemoDevice userDevice, OmemoDevice contactsDevicece, T_Sess session) throws IOException {
         HashMap<Integer, T_Sess> sessions = getCache(userDevice).sessions.get(contactsDevicece.getJid());
         if (sessions == null) {
             sessions = new HashMap<>();
@@ -391,7 +392,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     }
 
     @Override
-    public OmemoCachedDeviceList loadCachedDeviceList(OmemoDevice userDevice, BareJid contact) {
+    public OmemoCachedDeviceList loadCachedDeviceList(OmemoDevice userDevice, BareJid contact) throws IOException {
         OmemoCachedDeviceList list = getCache(userDevice).deviceLists.get(contact);
 
         if (list == null && persistent != null) {
@@ -407,7 +408,7 @@ public class CachingOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_Se
     @Override
     public void storeCachedDeviceList(OmemoDevice userDevice,
                                       BareJid contact,
-                                      OmemoCachedDeviceList deviceList) {
+                                      OmemoCachedDeviceList deviceList) throws IOException {
         getCache(userDevice).deviceLists.put(contact, new OmemoCachedDeviceList(deviceList));
 
         if (persistent != null) {
diff --git a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/FileBasedOmemoStore.java b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/FileBasedOmemoStore.java
index 6cfba87a8..612e955ff 100644
--- a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/FileBasedOmemoStore.java
+++ b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/FileBasedOmemoStore.java
@@ -1,6 +1,6 @@
 /**
  *
- * Copyright 2017 Paul Schaub
+ * Copyright 2017 Paul Schaub, 2019 Florian Schmaus.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,7 +21,6 @@ import java.io.DataOutputStream;
 import java.io.EOFException;
 import java.io.File;
 import java.io.FileInputStream;
-import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.util.Collections;
@@ -36,7 +35,6 @@ import java.util.TreeSet;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
-import org.jivesoftware.smack.util.CloseableUtil;
 import org.jivesoftware.smack.util.stringencoder.BareJidEncoder;
 
 import org.jivesoftware.smackx.omemo.exceptions.CorruptedOmemoKeyException;
@@ -67,13 +65,13 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
 
     @Override
     public T_IdKeyPair loadOmemoIdentityKeyPair(OmemoDevice userDevice)
-            throws CorruptedOmemoKeyException {
+            throws CorruptedOmemoKeyException, IOException {
         File identityKeyPairPath = hierarchy.getIdentityKeyPairPath(userDevice);
         return keyUtil().identityKeyPairFromBytes(readBytes(identityKeyPairPath));
     }
 
     @Override
-    public void storeOmemoIdentityKeyPair(OmemoDevice userDevice, T_IdKeyPair identityKeyPair) {
+    public void storeOmemoIdentityKeyPair(OmemoDevice userDevice, T_IdKeyPair identityKeyPair) throws IOException {
         File identityKeyPairPath = hierarchy.getIdentityKeyPairPath(userDevice);
         writeBytes(identityKeyPairPath, keyUtil().identityKeyPairToBytes(identityKeyPair));
     }
@@ -88,14 +86,14 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
 
     @Override
     public T_IdKey loadOmemoIdentityKey(OmemoDevice userDevice, OmemoDevice contactsDevice)
-            throws CorruptedOmemoKeyException {
+            throws CorruptedOmemoKeyException, IOException {
         File identityKeyPath = hierarchy.getContactsIdentityKeyPath(userDevice, contactsDevice);
         byte[] bytes = readBytes(identityKeyPath);
         return bytes != null ? keyUtil().identityKeyFromBytes(bytes) : null;
     }
 
     @Override
-    public void storeOmemoIdentityKey(OmemoDevice userDevice, OmemoDevice contactsDevice, T_IdKey t_idKey) {
+    public void storeOmemoIdentityKey(OmemoDevice userDevice, OmemoDevice contactsDevice, T_IdKey t_idKey) throws IOException {
         File identityKeyPath = hierarchy.getContactsIdentityKeyPath(userDevice, contactsDevice);
         writeBytes(identityKeyPath, keyUtil().identityKeyToBytes(t_idKey));
     }
@@ -126,46 +124,46 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
     }
 
     @Override
-    public void setDateOfLastReceivedMessage(OmemoDevice userDevice, OmemoDevice contactsDevice, Date date) {
+    public void setDateOfLastReceivedMessage(OmemoDevice userDevice, OmemoDevice contactsDevice, Date date) throws IOException {
         File lastMessageReceived = hierarchy.getLastMessageReceivedDatePath(userDevice, contactsDevice);
         writeLong(lastMessageReceived, date.getTime());
     }
 
     @Override
-    public Date getDateOfLastReceivedMessage(OmemoDevice userDevice, OmemoDevice contactsDevice) {
+    public Date getDateOfLastReceivedMessage(OmemoDevice userDevice, OmemoDevice contactsDevice) throws IOException {
         File lastMessageReceived = hierarchy.getLastMessageReceivedDatePath(userDevice, contactsDevice);
         Long date = readLong(lastMessageReceived);
         return date != null ? new Date(date) : null;
     }
 
     @Override
-    public void setDateOfLastDeviceIdPublication(OmemoDevice userDevice, OmemoDevice contactsDevice, Date date) {
+    public void setDateOfLastDeviceIdPublication(OmemoDevice userDevice, OmemoDevice contactsDevice, Date date) throws IOException {
         File lastDeviceIdPublished = hierarchy.getLastDeviceIdPublicationDatePath(userDevice, contactsDevice);
         writeLong(lastDeviceIdPublished, date.getTime());
     }
 
     @Override
-    public Date getDateOfLastDeviceIdPublication(OmemoDevice userDevice, OmemoDevice contactsDevice) {
+    public Date getDateOfLastDeviceIdPublication(OmemoDevice userDevice, OmemoDevice contactsDevice) throws IOException {
         File lastDeviceIdPublished = hierarchy.getLastDeviceIdPublicationDatePath(userDevice, contactsDevice);
         Long date = readLong(lastDeviceIdPublished);
         return date != null ? new Date(date) : null;
     }
 
     @Override
-    public void setDateOfLastSignedPreKeyRenewal(OmemoDevice userDevice, Date date) {
+    public void setDateOfLastSignedPreKeyRenewal(OmemoDevice userDevice, Date date) throws IOException {
         File lastSignedPreKeyRenewal = hierarchy.getLastSignedPreKeyRenewal(userDevice);
         writeLong(lastSignedPreKeyRenewal, date.getTime());
     }
 
     @Override
-    public Date getDateOfLastSignedPreKeyRenewal(OmemoDevice userDevice) {
+    public Date getDateOfLastSignedPreKeyRenewal(OmemoDevice userDevice) throws IOException {
         File lastSignedPreKeyRenewal = hierarchy.getLastSignedPreKeyRenewal(userDevice);
         Long date = readLong(lastSignedPreKeyRenewal);
         return date != null ? new Date(date) : null;
     }
 
     @Override
-    public T_PreKey loadOmemoPreKey(OmemoDevice userDevice, int preKeyId) {
+    public T_PreKey loadOmemoPreKey(OmemoDevice userDevice, int preKeyId) throws IOException {
         File preKeyPath = hierarchy.getPreKeyPath(userDevice, preKeyId);
         byte[] bytes = readBytes(preKeyPath);
 
@@ -181,7 +179,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
     }
 
     @Override
-    public void storeOmemoPreKey(OmemoDevice userDevice, int preKeyId, T_PreKey t_preKey) {
+    public void storeOmemoPreKey(OmemoDevice userDevice, int preKeyId, T_PreKey t_preKey) throws IOException {
         File preKeyPath = hierarchy.getPreKeyPath(userDevice, preKeyId);
         writeBytes(preKeyPath, keyUtil().preKeyToBytes(t_preKey));
     }
@@ -195,7 +193,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
     }
 
     @Override
-    public TreeMap<Integer, T_PreKey> loadOmemoPreKeys(OmemoDevice userDevice) {
+    public TreeMap<Integer, T_PreKey> loadOmemoPreKeys(OmemoDevice userDevice) throws IOException {
         File preKeyDirectory = hierarchy.getPreKeysDirectory(userDevice);
         TreeMap<Integer, T_PreKey> preKeys = new TreeMap<>();
 
@@ -221,7 +219,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
     }
 
     @Override
-    public T_SigPreKey loadOmemoSignedPreKey(OmemoDevice userDevice, int signedPreKeyId) {
+    public T_SigPreKey loadOmemoSignedPreKey(OmemoDevice userDevice, int signedPreKeyId) throws IOException {
         File signedPreKeyPath = new File(hierarchy.getSignedPreKeysDirectory(userDevice), Integer.toString(signedPreKeyId));
         byte[] bytes = readBytes(signedPreKeyPath);
         if (bytes != null) {
@@ -235,7 +233,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
     }
 
     @Override
-    public TreeMap<Integer, T_SigPreKey> loadOmemoSignedPreKeys(OmemoDevice userDevice) {
+    public TreeMap<Integer, T_SigPreKey> loadOmemoSignedPreKeys(OmemoDevice userDevice) throws IOException {
         File signedPreKeysDirectory = hierarchy.getSignedPreKeysDirectory(userDevice);
         TreeMap<Integer, T_SigPreKey> signedPreKeys = new TreeMap<>();
 
@@ -263,7 +261,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
     @Override
     public void storeOmemoSignedPreKey(OmemoDevice userDevice,
                                        int signedPreKeyId,
-                                       T_SigPreKey signedPreKey) {
+                                       T_SigPreKey signedPreKey) throws IOException {
         File signedPreKeyPath = new File(hierarchy.getSignedPreKeysDirectory(userDevice), Integer.toString(signedPreKeyId));
         writeBytes(signedPreKeyPath, keyUtil().signedPreKeyToBytes(signedPreKey));
     }
@@ -277,7 +275,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
     }
 
     @Override
-    public T_Sess loadRawSession(OmemoDevice userDevice, OmemoDevice contactsDevice) {
+    public T_Sess loadRawSession(OmemoDevice userDevice, OmemoDevice contactsDevice) throws IOException {
         File sessionPath = hierarchy.getContactsSessionPath(userDevice, contactsDevice);
         byte[] bytes = readBytes(sessionPath);
         if (bytes != null) {
@@ -291,7 +289,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
     }
 
     @Override
-    public HashMap<Integer, T_Sess> loadAllRawSessionsOf(OmemoDevice userDevice, BareJid contact) {
+    public HashMap<Integer, T_Sess> loadAllRawSessionsOf(OmemoDevice userDevice, BareJid contact) throws IOException {
         File contactsDirectory = hierarchy.getContactsDir(userDevice, contact);
         HashMap<Integer, T_Sess> sessions = new HashMap<>();
         String[] devices = contactsDirectory.list();
@@ -322,7 +320,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
     }
 
     @Override
-    public void storeRawSession(OmemoDevice userDevice, OmemoDevice contactsDevice, T_Sess session) {
+    public void storeRawSession(OmemoDevice userDevice, OmemoDevice contactsDevice, T_Sess session) throws IOException {
         File sessionPath = hierarchy.getContactsSessionPath(userDevice, contactsDevice);
         writeBytes(sessionPath, keyUtil().rawSessionToBytes(session));
     }
@@ -357,13 +355,13 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
     }
 
     @Override
-    public void storeOmemoMessageCounter(OmemoDevice userDevice, OmemoDevice contactsDevice, int counter) {
+    public void storeOmemoMessageCounter(OmemoDevice userDevice, OmemoDevice contactsDevice, int counter) throws IOException {
         File messageCounterFile = hierarchy.getDevicesMessageCounterPath(userDevice, contactsDevice);
         writeIntegers(messageCounterFile, Collections.singleton(counter));
     }
 
     @Override
-    public int loadOmemoMessageCounter(OmemoDevice userDevice, OmemoDevice contactsDevice) {
+    public int loadOmemoMessageCounter(OmemoDevice userDevice, OmemoDevice contactsDevice) throws IOException {
         File messageCounterFile = hierarchy.getDevicesMessageCounterPath(userDevice, contactsDevice);
         Set<Integer> integers = readIntegers(messageCounterFile);
 
@@ -375,7 +373,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
     }
 
     @Override
-    public OmemoCachedDeviceList loadCachedDeviceList(OmemoDevice userDevice, BareJid contact) {
+    public OmemoCachedDeviceList loadCachedDeviceList(OmemoDevice userDevice, BareJid contact) throws IOException {
         OmemoCachedDeviceList cachedDeviceList = new OmemoCachedDeviceList();
 
         if (contact == null) {
@@ -402,7 +400,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
     @Override
     public void storeCachedDeviceList(OmemoDevice userDevice,
                                       BareJid contact,
-                                      OmemoCachedDeviceList contactsDeviceList) {
+                                      OmemoCachedDeviceList contactsDeviceList) throws IOException {
         if (contact == null) {
             return;
         }
@@ -420,166 +418,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
         deleteDirectory(deviceDirectory);
     }
 
-    private static void writeLong(File target, long i) {
-        if (target == null) {
-            LOGGER.log(Level.WARNING, "Could not write long to null-path.");
-            return;
-        }
-
-        try {
-            FileHierarchy.createFile(target);
-        } catch (IOException e) {
-            LOGGER.log(Level.SEVERE, "Could not create file.", e);
-            return;
-        }
-
-        DataOutputStream out = null;
-        try {
-            out = new DataOutputStream(new FileOutputStream(target));
-            out.writeLong(i);
-
-        } catch (IOException e) {
-            LOGGER.log(Level.SEVERE, "Could not write longs to file.", e);
-        } finally {
-            CloseableUtil.maybeClose(out, LOGGER);
-        }
-    }
-
-    private static Long readLong(File target) {
-        if (target == null) {
-            LOGGER.log(Level.WARNING, "Could not read long from null-path.");
-            return null;
-        }
-
-        Long l;
-        DataInputStream in = null;
-
-        try {
-            in = new DataInputStream(new FileInputStream(target));
-            l = in.readLong();
-        } catch (FileNotFoundException e) {
-            l = null;
-        } catch (IOException e) {
-            LOGGER.log(Level.SEVERE, "Could not read long from file.", e);
-            return null;
-        } finally {
-            CloseableUtil.maybeClose(in, LOGGER);
-        }
-
-        return l;
-    }
-
-    private static void writeBytes(File target, byte[] bytes) {
-        if (target == null) {
-            LOGGER.log(Level.WARNING, "Could not write bytes to null-path.");
-            return;
-        }
-
-        // Create file
-        try {
-            FileHierarchy.createFile(target);
-        } catch (IOException e) {
-            LOGGER.log(Level.SEVERE, "Could not create file.", e);
-            return;
-        }
-
-        DataOutputStream out = null;
-
-        try {
-            out = new DataOutputStream(new FileOutputStream(target));
-            out.write(bytes);
-
-        } catch (IOException e) {
-            LOGGER.log(Level.SEVERE, "Could not write bytes to file.", e);
-        } finally {
-            CloseableUtil.maybeClose(out, LOGGER);
-        }
-    }
-
-    private static byte[] readBytes(File target) {
-        if (target == null) {
-            LOGGER.log(Level.WARNING, "Could not read bytes from null-path.");
-            return null;
-        }
-
-        byte[] b = null;
-        DataInputStream in = null;
-
-        try {
-            in = new DataInputStream(new FileInputStream(target));
-            b = new byte[(int) target.length()];
-            in.read(b);
-        } catch (FileNotFoundException e) {
-            b = null;
-        } catch (IOException e) {
-            LOGGER.log(Level.SEVERE, "Could not read bytes from file.", e);
-        } finally {
-            CloseableUtil.maybeClose(in, LOGGER);
-        }
-
-        return b;
-    }
-
-    private static void writeIntegers(File target, Set<Integer> integers) {
-        if (target == null) {
-            LOGGER.log(Level.WARNING, "Could not write integers to null-path.");
-            return;
-        }
-
-        DataOutputStream out = null;
-
-        try {
-            out = new DataOutputStream(new FileOutputStream(target));
-            for (int i : integers) {
-                out.writeInt(i);
-            }
-
-        } catch (IOException e) {
-            LOGGER.log(Level.SEVERE, "Could not write integers to file.", e);
-        } finally {
-            CloseableUtil.maybeClose(out, LOGGER);
-        }
-    }
-
-    private static Set<Integer> readIntegers(File target) {
-        if (target == null) {
-            LOGGER.log(Level.WARNING, "Could not read integers from null-path.");
-            return null;
-        }
-
-        HashSet<Integer> integers = new HashSet<>();
-        DataInputStream in = null;
-
-        try {
-            in = new DataInputStream(new FileInputStream(target));
-
-            try {
-                while (true) {
-                    integers.add(in.readInt());
-                }
-            } catch (EOFException e) {
-                // Reached end of the list.
-            }
-
-        } catch (FileNotFoundException e) {
-            integers = null;
-        } catch (IOException e) {
-            LOGGER.log(Level.SEVERE, "Could not read integers.", e);
-        } finally {
-            CloseableUtil.maybeClose(in, LOGGER);
-        }
-
-        return integers;
-    }
-
-    /**
-     * One day... *sheds a tear*
-     * TODO Use methods below once Smack's minimum Android API level is 19 or higher
-     */
-    /*
-    private static void writeLong(File target, long i)
-            throws IOException
-    {
+    private static void writeLong(File target, long i) throws IOException {
         if (target == null) {
             throw new IOException("Could not write long to null-path.");
         }
@@ -591,9 +430,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
         }
     }
 
-    private static Long readLong(File target)
-            throws IOException
-    {
+    private static Long readLong(File target) throws IOException {
         if (target == null) {
             throw new IOException("Could not read long from null-path.");
         }
@@ -607,9 +444,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
         }
     }
 
-    private static void writeBytes(File target, byte[] bytes)
-            throws IOException
-    {
+    private static void writeBytes(File target, byte[] bytes) throws IOException {
         if (target == null) {
             throw new IOException("Could not write bytes to null-path.");
         }
@@ -622,9 +457,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
         }
     }
 
-    private static byte[] readBytes(File target)
-            throws IOException
-    {
+    private static byte[] readBytes(File target) throws IOException {
         if (target == null) {
             throw new IOException("Could not read bytes from null-path.");
         }
@@ -641,9 +474,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
         return b;
     }
 
-    private static void writeIntegers(File target, Set<Integer> integers)
-            throws IOException
-    {
+    private static void writeIntegers(File target, Set<Integer> integers) throws IOException {
         if (target == null) {
             throw new IOException("Could not write integers to null-path.");
         }
@@ -657,9 +488,7 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
         }
     }
 
-    private static Set<Integer> readIntegers(File target)
-            throws IOException
-    {
+    private static Set<Integer> readIntegers(File target) throws IOException {
         if (target == null) {
             throw new IOException("Could not write integers to null-path.");
         }
@@ -682,7 +511,6 @@ public abstract class FileBasedOmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigP
 
         return integers;
     }
-     */
 
     /**
      * Delete a directory with all subdirectories.
diff --git a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoManager.java b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoManager.java
index 383dc3570..5b1807a8d 100644
--- a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoManager.java
+++ b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoManager.java
@@ -19,6 +19,7 @@ package org.jivesoftware.smackx.omemo;
 import static org.jivesoftware.smackx.omemo.util.OmemoConstants.OMEMO_NAMESPACE_V_AXOLOTL;
 import static org.jivesoftware.smackx.omemo.util.OmemoConstants.PEP_NODE_DEVICE_LIST_NOTIFY;
 
+import java.io.IOException;
 import java.security.NoSuchAlgorithmException;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -234,11 +235,12 @@ public final class OmemoManager extends Manager {
      * @throws XMPPException.XMPPErrorException
      * @throws SmackException.NotLoggedInException
      * @throws PubSubException.NotALeafNodeException
+     * @throws IOException
      */
     public void initialize()
             throws SmackException.NotLoggedInException, CorruptedOmemoKeyException, InterruptedException,
             SmackException.NoResponseException, SmackException.NotConnectedException, XMPPException.XMPPErrorException,
-            PubSubException.NotALeafNodeException {
+            PubSubException.NotALeafNodeException, IOException {
         synchronized (LOCK) {
             if (!connection().isAuthenticated()) {
                 throw new SmackException.NotLoggedInException();
@@ -279,8 +281,9 @@ public final class OmemoManager extends Manager {
      * @see #requestDeviceListUpdateFor(BareJid)
      * @param contact contact we want to get a set of device of.
      * @return set of known devices of that contact.
+     * @throws IOException
      */
-    public Set<OmemoDevice> getDevicesOf(BareJid contact) {
+    public Set<OmemoDevice> getDevicesOf(BareJid contact) throws IOException {
         OmemoCachedDeviceList list = getOmemoService().getOmemoStoreBackend().loadCachedDeviceList(getOwnDevice(), contact);
         HashSet<OmemoDevice> devices = new HashSet<>();
 
@@ -304,11 +307,12 @@ public final class OmemoManager extends Manager {
      * @throws SmackException.NotConnectedException
      * @throws SmackException.NoResponseException
      * @throws SmackException.NotLoggedInException
+     * @throws IOException
      */
     public OmemoMessage.Sent encrypt(BareJid recipient, String message)
             throws CryptoFailedException, UndecidedOmemoIdentityException,
             InterruptedException, SmackException.NotConnectedException,
-            SmackException.NoResponseException, SmackException.NotLoggedInException {
+            SmackException.NoResponseException, SmackException.NotLoggedInException, IOException {
         synchronized (LOCK) {
             Set<BareJid> recipients = new HashSet<>();
             recipients.add(recipient);
@@ -328,11 +332,12 @@ public final class OmemoManager extends Manager {
      * @throws SmackException.NotConnectedException
      * @throws SmackException.NoResponseException
      * @throws SmackException.NotLoggedInException
+     * @throws IOException
      */
     public OmemoMessage.Sent encrypt(Set<BareJid> recipients, String message)
             throws CryptoFailedException, UndecidedOmemoIdentityException,
             InterruptedException, SmackException.NotConnectedException,
-            SmackException.NoResponseException, SmackException.NotLoggedInException {
+            SmackException.NoResponseException, SmackException.NotLoggedInException, IOException {
         synchronized (LOCK) {
             LoggedInOmemoManager guard = new LoggedInOmemoManager(this);
             Set<OmemoDevice> devices = getDevicesOf(getOwnJid());
@@ -357,12 +362,13 @@ public final class OmemoManager extends Manager {
      * @throws SmackException.NoResponseException
      * @throws NoOmemoSupportException When the muc doesn't support OMEMO.
      * @throws SmackException.NotLoggedInException
+     * @throws IOException
      */
     public OmemoMessage.Sent encrypt(MultiUserChat muc, String message)
             throws UndecidedOmemoIdentityException, CryptoFailedException,
             XMPPException.XMPPErrorException, SmackException.NotConnectedException, InterruptedException,
             SmackException.NoResponseException, NoOmemoSupportException,
-            SmackException.NotLoggedInException {
+            SmackException.NotLoggedInException, IOException {
         synchronized (LOCK) {
             if (!multiUserChatSupportsOmemo(muc)) {
                 throw new NoOmemoSupportException();
@@ -390,10 +396,11 @@ public final class OmemoManager extends Manager {
      * @throws CorruptedOmemoKeyException if our or their key is corrupted
      * @throws NoRawSessionException if the message was not a preKeyMessage, but we had no session with the contact
      * @throws CryptoFailedException if decryption fails
+     * @throws IOException
      */
     public OmemoMessage.Received decrypt(BareJid sender, OmemoElement omemoElement)
             throws SmackException.NotLoggedInException, CorruptedOmemoKeyException, NoRawSessionException,
-            CryptoFailedException {
+            CryptoFailedException, IOException {
         LoggedInOmemoManager managerGuard = new LoggedInOmemoManager(this);
         return getOmemoService().decryptMessage(managerGuard, sender, omemoElement);
     }
@@ -404,9 +411,10 @@ public final class OmemoManager extends Manager {
      * @param mamQuery The MAM query
      * @return list of decrypted OmemoMessages
      * @throws SmackException.NotLoggedInException if the Manager is not authenticated.
+     * @throws IOException
      */
     public List<MessageOrOmemoMessage> decryptMamQueryResult(MamManager.MamQuery mamQuery)
-            throws SmackException.NotLoggedInException {
+            throws SmackException.NotLoggedInException, IOException {
         return new ArrayList<>(getOmemoService().decryptMamQueryResult(new LoggedInOmemoManager(this), mamQuery));
     }
 
@@ -486,11 +494,12 @@ public final class OmemoManager extends Manager {
      * @throws SmackException.NoResponseException
      * @throws NoSuchAlgorithmException
      * @throws SmackException.NotConnectedException
+     * @throws IOException
      */
     public void sendRatchetUpdateMessage(OmemoDevice recipient)
             throws SmackException.NotLoggedInException, CorruptedOmemoKeyException, InterruptedException,
             SmackException.NoResponseException, NoSuchAlgorithmException, SmackException.NotConnectedException,
-            CryptoFailedException, CannotEstablishOmemoSessionException {
+            CryptoFailedException, CannotEstablishOmemoSessionException, IOException {
         synchronized (LOCK) {
             Message message = new Message();
             message.setFrom(getOwnJid());
@@ -516,10 +525,11 @@ public final class OmemoManager extends Manager {
      * @throws SmackException.NoResponseException
      * @throws PubSubException.NotALeafNodeException
      * @throws XMPPException.XMPPErrorException
+     * @throws IOException
      */
     public boolean contactSupportsOmemo(BareJid contact)
             throws InterruptedException, PubSubException.NotALeafNodeException, XMPPException.XMPPErrorException,
-            SmackException.NotConnectedException, SmackException.NoResponseException {
+            SmackException.NotConnectedException, SmackException.NoResponseException, IOException {
         synchronized (LOCK) {
             OmemoCachedDeviceList deviceList = getOmemoService().refreshDeviceList(connection(), getOwnDevice(), contact);
             return !deviceList.getActiveDevices().isEmpty();
@@ -569,9 +579,10 @@ public final class OmemoManager extends Manager {
      * @return fingerprint
      * @throws SmackException.NotLoggedInException if we don't know our bareJid yet.
      * @throws CorruptedOmemoKeyException if our identityKey is corrupted.
+     * @throws IOException
      */
     public OmemoFingerprint getOwnFingerprint()
-            throws SmackException.NotLoggedInException, CorruptedOmemoKeyException {
+            throws SmackException.NotLoggedInException, CorruptedOmemoKeyException, IOException {
         synchronized (LOCK) {
             if (getOwnJid() == null) {
                 throw new SmackException.NotLoggedInException();
@@ -591,11 +602,12 @@ public final class OmemoManager extends Manager {
      * @throws SmackException.NotConnectedException
      * @throws InterruptedException
      * @throws SmackException.NoResponseException
+     * @throws IOException
      */
     public OmemoFingerprint getFingerprint(OmemoDevice device)
             throws CannotEstablishOmemoSessionException, SmackException.NotLoggedInException,
             CorruptedOmemoKeyException, SmackException.NotConnectedException, InterruptedException,
-            SmackException.NoResponseException {
+            SmackException.NoResponseException, IOException {
         synchronized (LOCK) {
             if (getOwnJid() == null) {
                 throw new SmackException.NotLoggedInException();
@@ -621,11 +633,12 @@ public final class OmemoManager extends Manager {
      * @throws SmackException.NotConnectedException
      * @throws InterruptedException
      * @throws SmackException.NoResponseException
+     * @throws IOException
      */
     public HashMap<OmemoDevice, OmemoFingerprint> getActiveFingerprints(BareJid contact)
             throws SmackException.NotLoggedInException, CorruptedOmemoKeyException,
             CannotEstablishOmemoSessionException, SmackException.NotConnectedException, InterruptedException,
-            SmackException.NoResponseException {
+            SmackException.NoResponseException, IOException {
         synchronized (LOCK) {
             if (getOwnJid() == null) {
                 throw new SmackException.NotLoggedInException();
@@ -692,10 +705,11 @@ public final class OmemoManager extends Manager {
      * @throws XMPPException.XMPPErrorException
      * @throws SmackException.NotConnectedException
      * @throws SmackException.NoResponseException
+     * @throws IOException
      */
     public void requestDeviceListUpdateFor(BareJid contact)
             throws InterruptedException, PubSubException.NotALeafNodeException, XMPPException.XMPPErrorException,
-            SmackException.NotConnectedException, SmackException.NoResponseException {
+            SmackException.NotConnectedException, SmackException.NoResponseException, IOException {
         synchronized (LOCK) {
             getOmemoService().refreshDeviceList(connection(), getOwnDevice(), contact);
         }
@@ -709,10 +723,11 @@ public final class OmemoManager extends Manager {
      * @throws XMPPException.XMPPErrorException
      * @throws SmackException.NotConnectedException
      * @throws SmackException.NoResponseException
+     * @throws IOException
      */
     public void purgeDeviceList()
             throws SmackException.NotLoggedInException, InterruptedException, XMPPException.XMPPErrorException,
-            SmackException.NotConnectedException, SmackException.NoResponseException {
+            SmackException.NotConnectedException, SmackException.NoResponseException, IOException {
         synchronized (LOCK) {
             getOmemoService().purgeDeviceList(new LoggedInOmemoManager(this));
         }
@@ -729,10 +744,11 @@ public final class OmemoManager extends Manager {
      * @throws SmackException.NotConnectedException XMPP error
      * @throws SmackException.NoResponseException XMPP error
      * @throws SmackException.NotLoggedInException
+     * @throws IOException
      */
     public void rotateSignedPreKey()
             throws CorruptedOmemoKeyException, SmackException.NotLoggedInException, XMPPException.XMPPErrorException,
-            SmackException.NotConnectedException, InterruptedException, SmackException.NoResponseException {
+            SmackException.NotConnectedException, InterruptedException, SmackException.NoResponseException, IOException {
         synchronized (LOCK) {
             if (!connection().isAuthenticated()) {
                 throw new SmackException.NotLoggedInException();
@@ -956,8 +972,8 @@ public final class OmemoManager extends Manager {
                     try {
                         getOmemoService().onOmemoMessageStanzaReceived(packet,
                                 new LoggedInOmemoManager(OmemoManager.this));
-                    } catch (SmackException.NotLoggedInException e) {
-                        LOGGER.warning("Received OMEMO stanza while being offline: " + e);
+                    } catch (SmackException.NotLoggedInException | IOException e) {
+                        LOGGER.log(Level.SEVERE, "Exception while processing OMEMO stanza", e);
                     }
                 }
             });
@@ -979,8 +995,8 @@ public final class OmemoManager extends Manager {
                         try {
                             getOmemoService().onOmemoCarbonCopyReceived(direction, carbonCopy, wrappingMessage,
                                     new LoggedInOmemoManager(OmemoManager.this));
-                        } catch (SmackException.NotLoggedInException e) {
-                            LOGGER.warning("Received OMEMO carbon copy while being offline: " + e);
+                        } catch (SmackException.NotLoggedInException | IOException e) {
+                            LOGGER.log(Level.SEVERE, "Exception while processing OMEMO stanza", e);
                         }
                     }
                 }
@@ -1018,14 +1034,23 @@ public final class OmemoManager extends Manager {
                     }
 
                     // Device List <list>
+                    OmemoCachedDeviceList deviceList;
                     OmemoDeviceListElement receivedDeviceList = (OmemoDeviceListElement) payloadItem.getPayload();
-                    getOmemoService().getOmemoStoreBackend().mergeCachedDeviceList(getOwnDevice(), from, receivedDeviceList);
+                    try {
+                        getOmemoService().getOmemoStoreBackend().mergeCachedDeviceList(getOwnDevice(), from,
+                                        receivedDeviceList);
 
-                    if (!from.asBareJid().equals(getOwnJid())) {
+                        if (!from.asBareJid().equals(getOwnJid())) {
+                            continue;
+                        }
+
+                        deviceList = getOmemoService().cleanUpDeviceList(getOwnDevice());
+                    } catch (IOException e) {
+                        LOGGER.log(Level.SEVERE,
+                                        "IOException while processing OMEMO PEP device updates. Message: " + message,
+                                        e);
                         continue;
                     }
-
-                    OmemoCachedDeviceList deviceList = getOmemoService().cleanUpDeviceList(getOwnDevice());
                     final OmemoDeviceListElement_VAxolotl newDeviceList = new OmemoDeviceListElement_VAxolotl(deviceList);
 
                     if (!newDeviceList.copyDeviceIds().equals(receivedDeviceList.copyDeviceIds())) {
diff --git a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoRatchet.java b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoRatchet.java
index 28ffc50ef..7ad0f6b6e 100644
--- a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoRatchet.java
+++ b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoRatchet.java
@@ -16,6 +16,7 @@
  */
 package org.jivesoftware.smackx.omemo;
 
+import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.List;
@@ -65,10 +66,11 @@ public abstract class OmemoRatchet<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @throws NoRawSessionException when no double ratchet session was found.
      * @throws CryptoFailedException
      * @throws UntrustedOmemoIdentityException
+     * @throws IOException
      */
     public abstract byte[] doubleRatchetDecrypt(OmemoDevice sender, byte[] encryptedKey)
             throws CorruptedOmemoKeyException, NoRawSessionException, CryptoFailedException,
-            UntrustedOmemoIdentityException;
+            UntrustedOmemoIdentityException, IOException;
 
     /**
      * Encrypt a messageKey with the double ratchet session of the recipient.
@@ -86,9 +88,10 @@ public abstract class OmemoRatchet<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @return tuple of cipher generated from the unpacked message key and the auth-tag
      * @throws CryptoFailedException if decryption using the double ratchet fails
      * @throws NoRawSessionException if we have no session, but the element was NOT a PreKeyMessage
+     * @throws IOException
      */
     CipherAndAuthTag retrieveMessageKeyAndAuthTag(OmemoDevice sender, OmemoElement element) throws CryptoFailedException,
-            NoRawSessionException {
+            NoRawSessionException, IOException {
         int keyId = omemoManager.getDeviceId();
         byte[] unpackedKey = null;
         List<CryptoFailedException> decryptExceptions = new ArrayList<>();
diff --git a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoService.java b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoService.java
index 91eb51034..1130e63fc 100644
--- a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoService.java
+++ b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoService.java
@@ -19,6 +19,7 @@ package org.jivesoftware.smackx.omemo;
 import static org.jivesoftware.smackx.omemo.util.OmemoConstants.Crypto.KEYLENGTH;
 import static org.jivesoftware.smackx.omemo.util.OmemoConstants.Crypto.KEYTYPE;
 
+import java.io.IOException;
 import java.security.InvalidAlgorithmParameterException;
 import java.security.InvalidKeyException;
 import java.security.NoSuchAlgorithmException;
@@ -234,11 +235,12 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @throws SmackException.NotConnectedException
      * @throws SmackException.NoResponseException
      * @throws PubSubException.NotALeafNodeException
+     * @throws IOException
      */
     void init(OmemoManager.LoggedInOmemoManager managerGuard)
             throws InterruptedException, CorruptedOmemoKeyException, XMPPException.XMPPErrorException,
             SmackException.NotConnectedException, SmackException.NoResponseException,
-            PubSubException.NotALeafNodeException {
+            PubSubException.NotALeafNodeException, IOException {
 
         OmemoManager manager = managerGuard.get();
         OmemoDevice userDevice = manager.getOwnDevice();
@@ -273,12 +275,13 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @throws CorruptedOmemoKeyException if our IdentityKeyPair is corrupted.
      * @throws SmackException.NotConnectedException
      * @throws CannotEstablishOmemoSessionException if session negotiation fails.
+     * @throws IOException
      */
     OmemoElement createRatchetUpdateElement(OmemoManager.LoggedInOmemoManager managerGuard,
                                             OmemoDevice contactsDevice)
             throws InterruptedException, SmackException.NoResponseException, CorruptedOmemoKeyException,
             SmackException.NotConnectedException, CannotEstablishOmemoSessionException, NoSuchAlgorithmException,
-            CryptoFailedException {
+            CryptoFailedException, IOException {
 
         OmemoManager manager = managerGuard.get();
         OmemoDevice userDevice = manager.getOwnDevice();
@@ -334,6 +337,7 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @throws SmackException.NoResponseException
      * @throws UndecidedOmemoIdentityException if the list of recipient devices contains undecided devices
      * @throws CryptoFailedException if we are lacking some crypto primitives
+     * @throws IOException
      */
     private OmemoMessage.Sent encrypt(OmemoManager.LoggedInOmemoManager managerGuard,
                                       Set<OmemoDevice> contactsDevices,
@@ -341,7 +345,7 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
                                       byte[] iv,
                                       String message)
             throws SmackException.NotConnectedException, InterruptedException, SmackException.NoResponseException,
-            UndecidedOmemoIdentityException, CryptoFailedException {
+            UndecidedOmemoIdentityException, CryptoFailedException, IOException {
 
         OmemoManager manager = managerGuard.get();
         OmemoDevice userDevice = manager.getOwnDevice();
@@ -435,11 +439,12 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @throws CorruptedOmemoKeyException if the identityKey of the sender is damaged.
      * @throws CryptoFailedException if decryption fails.
      * @throws NoRawSessionException if we have no session with the device and it sent a normal (non-preKey) message.
+     * @throws IOException
      */
     OmemoMessage.Received decryptMessage(OmemoManager.LoggedInOmemoManager managerGuard,
                                          BareJid senderJid,
                                          OmemoElement omemoElement)
-            throws CorruptedOmemoKeyException, CryptoFailedException, NoRawSessionException {
+            throws CorruptedOmemoKeyException, CryptoFailedException, NoRawSessionException, IOException {
 
         OmemoManager manager = managerGuard.get();
         int senderId = omemoElement.getHeader().getSid();
@@ -488,13 +493,14 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @throws CryptoFailedException if we are lacking some cryptographic algorithms
      * @throws SmackException.NotConnectedException
      * @throws SmackException.NoResponseException
+     * @throws IOException
      */
     OmemoMessage.Sent createKeyTransportElement(OmemoManager.LoggedInOmemoManager managerGuard,
                                                 Set<OmemoDevice> contactsDevices,
                                                 byte[] key,
                                                 byte[] iv)
             throws InterruptedException, UndecidedOmemoIdentityException, CryptoFailedException,
-            SmackException.NotConnectedException, SmackException.NoResponseException {
+            SmackException.NotConnectedException, SmackException.NoResponseException, IOException {
         return encrypt(managerGuard, contactsDevices, key, iv, null);
     }
 
@@ -511,12 +517,13 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @throws CryptoFailedException if we are lacking some cryptographic algorithms
      * @throws SmackException.NotConnectedException
      * @throws SmackException.NoResponseException
+     * @throws IOException
      */
     OmemoMessage.Sent createOmemoMessage(OmemoManager.LoggedInOmemoManager managerGuard,
                                          Set<OmemoDevice> contactsDevices,
                                          String message)
             throws InterruptedException, UndecidedOmemoIdentityException, CryptoFailedException,
-            SmackException.NotConnectedException, SmackException.NoResponseException {
+            SmackException.NotConnectedException, SmackException.NoResponseException, IOException {
 
         byte[] key, iv;
         iv = OmemoMessageBuilder.generateIv();
@@ -643,10 +650,11 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @throws XMPPException.XMPPErrorException
      * @throws SmackException.NotConnectedException
      * @throws SmackException.NoResponseException
+     * @throws IOException
      */
     private void refreshAndRepublishDeviceList(XMPPConnection connection, OmemoDevice userDevice)
             throws InterruptedException, PubSubException.NotALeafNodeException, XMPPException.XMPPErrorException,
-            SmackException.NotConnectedException, SmackException.NoResponseException {
+            SmackException.NotConnectedException, SmackException.NoResponseException, IOException {
 
         // refreshOmemoDeviceList;
         OmemoDeviceListElement publishedList;
@@ -685,8 +693,9 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      *
      * @param userDevice
      * @return
+     * @throws IOException
      */
-    OmemoCachedDeviceList cleanUpDeviceList(OmemoDevice userDevice) {
+    OmemoCachedDeviceList cleanUpDeviceList(OmemoDevice userDevice) throws IOException {
         OmemoCachedDeviceList cachedDeviceList;
 
         // Delete stale devices if allowed and necessary
@@ -719,10 +728,11 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @throws XMPPException.XMPPErrorException
      * @throws SmackException.NotConnectedException
      * @throws SmackException.NoResponseException
+     * @throws IOException
      */
     OmemoCachedDeviceList refreshDeviceList(XMPPConnection connection, OmemoDevice userDevice, BareJid contact)
             throws InterruptedException, PubSubException.NotALeafNodeException, XMPPException.XMPPErrorException,
-            SmackException.NotConnectedException, SmackException.NoResponseException {
+            SmackException.NotConnectedException, SmackException.NoResponseException, IOException {
         // refreshOmemoDeviceList;
         OmemoDeviceListElement publishedList;
         try {
@@ -790,11 +800,12 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @throws SmackException.NotConnectedException
      * @throws InterruptedException
      * @throws SmackException.NoResponseException
+     * @throws IOException
      */
     private Set<OmemoDevice> buildMissingSessionsWithDevices(XMPPConnection connection,
                                                              OmemoDevice userDevice,
                                                              Set<OmemoDevice> devices)
-            throws SmackException.NotConnectedException, InterruptedException, SmackException.NoResponseException {
+            throws SmackException.NotConnectedException, InterruptedException, SmackException.NoResponseException, IOException {
 
         Set<OmemoDevice> devicesWithSession = new HashSet<>();
         for (OmemoDevice device : devices) {
@@ -828,8 +839,9 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @param callback OmemoTrustCallback to query the trust decisions from
      * @param devices set of OmemoDevices
      * @return set of OmemoDevices which contains all devices from the set devices, which are undecided
+     * @throws IOException
      */
-    private Set<OmemoDevice> getUndecidedDevices(OmemoDevice userDevice, OmemoTrustCallback callback, Set<OmemoDevice> devices) {
+    private Set<OmemoDevice> getUndecidedDevices(OmemoDevice userDevice, OmemoTrustCallback callback, Set<OmemoDevice> devices) throws IOException {
         Set<OmemoDevice> undecidedDevices = new HashSet<>();
 
         for (OmemoDevice device : devices) {
@@ -858,8 +870,9 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @param userDevice our OmemoDevice.
      * @param contactsDevice OmemoDevice of the contact.
      * @return true if userDevice has session with contactsDevice.
+     * @throws IOException
      */
-    private boolean hasSession(OmemoDevice userDevice, OmemoDevice contactsDevice) {
+    private boolean hasSession(OmemoDevice userDevice, OmemoDevice contactsDevice) throws IOException {
         return getOmemoStoreBackend().loadRawSession(userDevice, contactsDevice) != null;
     }
 
@@ -881,8 +894,9 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      *
      * @param userDevice our OmemoDevice
      * @return true if rotation is necessary
+     * @throws IOException
      */
-    private boolean shouldRotateSignedPreKey(OmemoDevice userDevice) {
+    private boolean shouldRotateSignedPreKey(OmemoDevice userDevice) throws IOException {
         if (!OmemoConfiguration.getRenewOldSignedPreKeys()) {
             return false;
         }
@@ -909,8 +923,9 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      *
      * @param userDevice our OmemoDevice
      * @return our altered deviceList with stale devices marked as inactive.
+     * @throws IOException
      */
-    private OmemoCachedDeviceList deleteStaleDevices(OmemoDevice userDevice) {
+    private OmemoCachedDeviceList deleteStaleDevices(OmemoDevice userDevice) throws IOException {
         OmemoCachedDeviceList deviceList = getOmemoStoreBackend().loadCachedDeviceList(userDevice);
         int maxAgeHours = OmemoConfiguration.getDeleteStaleDevicesAfterHours();
         return removeStaleDevicesFromDeviceList(userDevice, userDevice.getJid(), deviceList, maxAgeHours);
@@ -928,11 +943,12 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @param contact subjects BareJid.
      * @param contactsDeviceList subjects deviceList.
      * @return copy of subjects deviceList with stale devices marked as inactive.
+     * @throws IOException
      */
     private OmemoCachedDeviceList removeStaleDevicesFromDeviceList(OmemoDevice userDevice,
                                                                    BareJid contact,
                                                                    OmemoCachedDeviceList contactsDeviceList,
-                                                                   int maxAgeHours) {
+                                                                   int maxAgeHours) throws IOException {
         OmemoCachedDeviceList deviceList = new OmemoCachedDeviceList(contactsDeviceList); // Don't work on original list.
 
         // Iterate through original list, but modify copy instead
@@ -1024,9 +1040,10 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @param managerGuard authenticated OmemoManager.
      * @param mamQuery Mam archive query
      * @return list of {@link MessageOrOmemoMessage}s.
+     * @throws IOException
      */
     List<MessageOrOmemoMessage> decryptMamQueryResult(OmemoManager.LoggedInOmemoManager managerGuard,
-                                                      MamManager.MamQuery mamQuery) {
+                                                      MamManager.MamQuery mamQuery) throws IOException {
         List<MessageOrOmemoMessage> result = new ArrayList<>();
         for (Message message : mamQuery.getMessages()) {
             if (OmemoManager.stanzaContainsOmemoElement(message)) {
@@ -1055,7 +1072,7 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
     public void onOmemoCarbonCopyReceived(CarbonExtension.Direction direction,
                                           Message carbonCopy,
                                           Message wrappingMessage,
-                                          OmemoManager.LoggedInOmemoManager managerGuard) {
+                                          OmemoManager.LoggedInOmemoManager managerGuard) throws IOException {
         OmemoManager manager = managerGuard.get();
         // Avoid the ratchet being manipulated and the bundle being published multiple times simultaneously
         synchronized (manager.LOCK) {
@@ -1110,7 +1127,7 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
     }
 
     @Override
-    public void onOmemoMessageStanzaReceived(Stanza stanza, OmemoManager.LoggedInOmemoManager managerGuard) {
+    public void onOmemoMessageStanzaReceived(Stanza stanza, OmemoManager.LoggedInOmemoManager managerGuard) throws IOException {
         OmemoManager manager = managerGuard.get();
         // Avoid the ratchet being manipulated and the bundle being published multiple times simultaneously
         synchronized (manager.LOCK) {
@@ -1197,8 +1214,9 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @param stanza stanza
      * @param managerGuard authenticated OmemoManager
      * @return decrypted OmemoMessage or null
+     * @throws IOException
      */
-    OmemoMessage.Received decryptStanza(Stanza stanza, OmemoManager.LoggedInOmemoManager managerGuard) {
+    OmemoMessage.Received decryptStanza(Stanza stanza, OmemoManager.LoggedInOmemoManager managerGuard) throws IOException {
         OmemoManager manager = managerGuard.get();
         // Avoid the ratchet being manipulated and the bundle being published multiple times simultaneously
         synchronized (manager.LOCK) {
@@ -1275,9 +1293,10 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      *
      * @param managerGuard authenticated OmemoManager.
      * @param brokenDevice device which session broke.
+     * @throws IOException
      */
     private void repairBrokenSessionWithPreKeyMessage(OmemoManager.LoggedInOmemoManager managerGuard,
-                                                      OmemoDevice brokenDevice) {
+                                                      OmemoDevice brokenDevice) throws IOException {
 
         LOGGER.log(Level.WARNING, "Attempt to repair the session by sending a fresh preKey message to "
                 + brokenDevice);
@@ -1307,11 +1326,12 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @throws SmackException.NotConnectedException
      * @throws CryptoFailedException if encryption fails (should not happen though, but who knows...)
      * @throws CannotEstablishOmemoSessionException if we cannot establish a session with contactsDevice.
+     * @throws IOException
      */
     private void sendRatchetUpdate(OmemoManager.LoggedInOmemoManager managerGuard, OmemoDevice contactsDevice)
             throws CorruptedOmemoKeyException, InterruptedException, SmackException.NoResponseException,
             NoSuchAlgorithmException, SmackException.NotConnectedException, CryptoFailedException,
-            CannotEstablishOmemoSessionException {
+            CannotEstablishOmemoSessionException, IOException {
 
         OmemoManager manager = managerGuard.get();
         OmemoElement ratchetUpdate = createRatchetUpdateElement(managerGuard, contactsDevice);
@@ -1350,10 +1370,11 @@ public abstract class OmemoService<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey,
      * @throws XMPPException.XMPPErrorException
      * @throws SmackException.NotConnectedException
      * @throws SmackException.NoResponseException
+     * @throws IOException
      */
     public void purgeDeviceList(OmemoManager.LoggedInOmemoManager managerGuard)
             throws InterruptedException, XMPPException.XMPPErrorException, SmackException.NotConnectedException,
-            SmackException.NoResponseException {
+            SmackException.NoResponseException, IOException {
 
         OmemoManager omemoManager = managerGuard.get();
         OmemoDevice userDevice = omemoManager.getOwnDevice();
diff --git a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoStore.java b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoStore.java
index 033db6994..9da60104e 100644
--- a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoStore.java
+++ b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/OmemoStore.java
@@ -18,6 +18,7 @@ package org.jivesoftware.smackx.omemo;
 
 import static org.jivesoftware.smackx.omemo.util.OmemoConstants.PRE_KEY_COUNT_PER_BUNDLE;
 
+import java.io.IOException;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.Map;
@@ -78,8 +79,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice    our current device.
      * @param id            deviceId to check for.
      * @return true if list did not contain our id, else false
+     * @throws IOException
      */
-    boolean isAvailableDeviceId(OmemoDevice userDevice, int id) {
+    boolean isAvailableDeviceId(OmemoDevice userDevice, int id) throws IOException {
         LOGGER.log(Level.INFO, "Check if id " + id + " is available...");
 
         // Lookup local cached device list
@@ -101,8 +103,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @param contact Contact we received the list from.
      * @param list    List we received.
+     * @throws IOException
      */
-    OmemoCachedDeviceList mergeCachedDeviceList(OmemoDevice userDevice, BareJid contact, OmemoDeviceListElement list) {
+    OmemoCachedDeviceList mergeCachedDeviceList(OmemoDevice userDevice, BareJid contact, OmemoDeviceListElement list) throws IOException {
         OmemoCachedDeviceList cached = loadCachedDeviceList(userDevice, contact);
 
         if (cached == null) {
@@ -131,10 +134,11 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      *
      * @param userDevice our OmemoDevice.
      * @throws CorruptedOmemoKeyException when our identityKey is invalid.
+     * @throws IOException
      * @throws IllegalStateException when our IdentityKeyPair is null.
      */
     void changeSignedPreKey(OmemoDevice userDevice)
-            throws CorruptedOmemoKeyException {
+            throws CorruptedOmemoKeyException, IOException {
 
         T_IdKeyPair idKeyPair = loadOmemoIdentityKeyPair(userDevice);
         if (idKeyPair == null) {
@@ -159,8 +163,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * Remove the oldest signedPreKey until there are only MAX_NUMBER_OF_STORED_SIGNED_PREKEYS left.
      *
      * @param userDevice our OmemoDevice.
+     * @throws IOException
      */
-    private void removeOldSignedPreKeys(OmemoDevice userDevice) {
+    private void removeOldSignedPreKeys(OmemoDevice userDevice) throws IOException {
         if (OmemoConfiguration.getMaxNumberOfStoredSignedPreKeys() <= 0) {
             return;
         }
@@ -181,9 +186,10 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @return OmemoBundleElement
      * @throws CorruptedOmemoKeyException when a key could not be loaded
+     * @throws IOException
      */
     OmemoBundleElement_VAxolotl packOmemoBundle(OmemoDevice userDevice)
-            throws CorruptedOmemoKeyException {
+            throws CorruptedOmemoKeyException, IOException {
 
         int currentSignedPreKeyId = loadCurrentOmemoSignedPreKeyId(userDevice);
         T_SigPreKey currentSignedPreKey = loadOmemoSignedPreKeys(userDevice).get(currentSignedPreKeyId);
@@ -201,9 +207,10 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * Replenish our supply of keys. If we are missing any type of keys, generate them fresh.
      * @param userDevice
      * @throws CorruptedOmemoKeyException
+     * @throws IOException
      */
     public void replenishKeys(OmemoDevice userDevice)
-            throws CorruptedOmemoKeyException {
+            throws CorruptedOmemoKeyException, IOException {
 
         T_IdKeyPair identityKeyPair = loadOmemoIdentityKeyPair(userDevice);
         if (identityKeyPair == null) {
@@ -244,9 +251,10 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @return identityKeyPair
      * @throws CorruptedOmemoKeyException Thrown, if the stored key is damaged (*hands up* not my fault!)
+     * @throws IOException
      */
     public abstract T_IdKeyPair loadOmemoIdentityKeyPair(OmemoDevice userDevice)
-            throws CorruptedOmemoKeyException;
+            throws CorruptedOmemoKeyException, IOException;
 
     /**
      * Store our identityKeyPair in storage. It would be a cool feature, if the key could be stored in a encrypted
@@ -254,8 +262,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      *
      * @param userDevice our OmemoDevice.
      * @param identityKeyPair identityKeyPair
+     * @throws IOException
      */
-    public abstract void storeOmemoIdentityKeyPair(OmemoDevice userDevice, T_IdKeyPair identityKeyPair);
+    public abstract void storeOmemoIdentityKeyPair(OmemoDevice userDevice, T_IdKeyPair identityKeyPair) throws IOException;
 
     /**
      * Remove the identityKeyPair of a user.
@@ -270,9 +279,10 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param contactsDevice the device of which we want to load the identityKey.
      * @return identityKey
      * @throws CorruptedOmemoKeyException when the key in question is corrupted and cant be deserialized.
+     * @throws IOException
      */
     public abstract T_IdKey loadOmemoIdentityKey(OmemoDevice userDevice, OmemoDevice contactsDevice)
-            throws CorruptedOmemoKeyException;
+            throws CorruptedOmemoKeyException, IOException;
 
     /**
      * Store the public identityKey of the device.
@@ -280,8 +290,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @param contactsDevice device.
      * @param contactsKey    identityKey belonging to the contactsDevice.
+     * @throws IOException
      */
-    public abstract void storeOmemoIdentityKey(OmemoDevice userDevice, OmemoDevice contactsDevice, T_IdKey contactsKey);
+    public abstract void storeOmemoIdentityKey(OmemoDevice userDevice, OmemoDevice contactsDevice, T_IdKey contactsKey) throws IOException;
 
     /**
      * Removes the identityKey of a device.
@@ -298,8 +309,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our omemoDevice.
      * @param contactsDevice device of which we want to set the message counter.
      * @param counter counter value.
+     * @throws IOException
      */
-    public abstract void storeOmemoMessageCounter(OmemoDevice userDevice, OmemoDevice contactsDevice, int counter);
+    public abstract void storeOmemoMessageCounter(OmemoDevice userDevice, OmemoDevice contactsDevice, int counter) throws IOException;
 
     /**
      * Return the current value of the message counter.
@@ -309,8 +321,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our omemoDevice
      * @param contactsDevice device of which we want to get the message counter.
      * @return counter value.
+     * @throws IOException
      */
-    public abstract int loadOmemoMessageCounter(OmemoDevice userDevice, OmemoDevice contactsDevice);
+    public abstract int loadOmemoMessageCounter(OmemoDevice userDevice, OmemoDevice contactsDevice) throws IOException;
 
     /**
      * Set the date of the last message that was received from a device.
@@ -318,8 +331,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice omemoManager of our device.
      * @param contactsDevice device in question
      * @param date date of the last received message
+     * @throws IOException
      */
-    public abstract void setDateOfLastReceivedMessage(OmemoDevice userDevice, OmemoDevice contactsDevice, Date date);
+    public abstract void setDateOfLastReceivedMessage(OmemoDevice userDevice, OmemoDevice contactsDevice, Date date) throws IOException;
 
     /**
      * Return the date of the last message that was received from device 'from'.
@@ -327,8 +341,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @param contactsDevice device in question
      * @return date if existent, null
+     * @throws IOException
      */
-    public abstract Date getDateOfLastReceivedMessage(OmemoDevice userDevice, OmemoDevice contactsDevice);
+    public abstract Date getDateOfLastReceivedMessage(OmemoDevice userDevice, OmemoDevice contactsDevice) throws IOException;
 
     /**
      * Set the date of the last time the deviceId was published. This method only gets called, when the deviceId
@@ -337,8 +352,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice
      * @param contactsDevice OmemoDevice in question
      * @param date date of the last publication after not being published
+     * @throws IOException
      */
-    public abstract void setDateOfLastDeviceIdPublication(OmemoDevice userDevice, OmemoDevice contactsDevice, Date date);
+    public abstract void setDateOfLastDeviceIdPublication(OmemoDevice userDevice, OmemoDevice contactsDevice, Date date) throws IOException;
 
     /**
      * Return the date of the last time the deviceId was published after previously being not published.
@@ -347,24 +363,27 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice
      * @param contactsDevice OmemoDevice in question
      * @return date of the last publication after not being published
+     * @throws IOException
      */
-    public abstract Date getDateOfLastDeviceIdPublication(OmemoDevice userDevice, OmemoDevice contactsDevice);
+    public abstract Date getDateOfLastDeviceIdPublication(OmemoDevice userDevice, OmemoDevice contactsDevice) throws IOException;
 
     /**
      * Set the date of the last time the signed preKey was renewed.
      *
      * @param userDevice our OmemoDevice.
      * @param date date
+     * @throws IOException
      */
-    public abstract void setDateOfLastSignedPreKeyRenewal(OmemoDevice userDevice, Date date);
+    public abstract void setDateOfLastSignedPreKeyRenewal(OmemoDevice userDevice, Date date) throws IOException;
 
     /**
      * Get the date of the last time the signed preKey was renewed.
      *
      * @param userDevice our OmemoDevice.
      * @return date if existent, otherwise null
+     * @throws IOException
      */
-    public abstract Date getDateOfLastSignedPreKeyRenewal(OmemoDevice userDevice);
+    public abstract Date getDateOfLastSignedPreKeyRenewal(OmemoDevice userDevice) throws IOException;
 
     /**
      * Generate 'count' new PreKeys beginning with id 'startId'.
@@ -384,8 +403,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @param preKeyId id of the key to be loaded
      * @return loaded preKey
+     * @throws IOException
      */
-    public abstract T_PreKey loadOmemoPreKey(OmemoDevice userDevice, int preKeyId);
+    public abstract T_PreKey loadOmemoPreKey(OmemoDevice userDevice, int preKeyId) throws IOException;
 
     /**
      * Store a PreKey in storage.
@@ -393,16 +413,18 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @param preKeyId id of the key
      * @param preKey   key
+     * @throws IOException
      */
-    public abstract void storeOmemoPreKey(OmemoDevice userDevice, int preKeyId, T_PreKey preKey);
+    public abstract void storeOmemoPreKey(OmemoDevice userDevice, int preKeyId, T_PreKey preKey) throws IOException;
 
     /**
      * Store a whole bunch of preKeys.
      *
      * @param userDevice our OmemoDevice.
      * @param preKeyHashMap HashMap of preKeys
+     * @throws IOException
      */
-    public void storeOmemoPreKeys(OmemoDevice userDevice, TreeMap<Integer, T_PreKey> preKeyHashMap) {
+    public void storeOmemoPreKeys(OmemoDevice userDevice, TreeMap<Integer, T_PreKey> preKeyHashMap) throws IOException {
         for (Map.Entry<Integer, T_PreKey> entry : preKeyHashMap.entrySet()) {
             storeOmemoPreKey(userDevice, entry.getKey(), entry.getValue());
         }
@@ -422,8 +444,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      *
      * @param userDevice our OmemoDevice.
      * @return Map containing our preKeys
+     * @throws IOException
      */
-    public abstract TreeMap<Integer, T_PreKey> loadOmemoPreKeys(OmemoDevice userDevice);
+    public abstract TreeMap<Integer, T_PreKey> loadOmemoPreKeys(OmemoDevice userDevice) throws IOException;
 
     /**
      * Return the signedPreKey with the id 'singedPreKeyId'.
@@ -431,10 +454,11 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @param signedPreKeyId id of the key
      * @return key
+     * @throws IOException
      */
-    public abstract T_SigPreKey loadOmemoSignedPreKey(OmemoDevice userDevice, int signedPreKeyId);
+    public abstract T_SigPreKey loadOmemoSignedPreKey(OmemoDevice userDevice, int signedPreKeyId) throws IOException;
 
-    public int loadCurrentOmemoSignedPreKeyId(OmemoDevice userDevice) {
+    public int loadCurrentOmemoSignedPreKeyId(OmemoDevice userDevice) throws IOException {
         return loadOmemoSignedPreKeys(userDevice).lastKey();
     }
 
@@ -443,8 +467,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      *
      * @param userDevice our OmemoDevice.
      * @return HashMap of our singedPreKeys
+     * @throws IOException
      */
-    public abstract TreeMap<Integer, T_SigPreKey> loadOmemoSignedPreKeys(OmemoDevice userDevice);
+    public abstract TreeMap<Integer, T_SigPreKey> loadOmemoSignedPreKeys(OmemoDevice userDevice) throws IOException;
 
     /**
      * Generate a new signed preKey.
@@ -465,8 +490,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @param signedPreKeyId id of the signedPreKey
      * @param signedPreKey   the key itself
+     * @throws IOException
      */
-    public abstract void storeOmemoSignedPreKey(OmemoDevice userDevice, int signedPreKeyId, T_SigPreKey signedPreKey);
+    public abstract void storeOmemoSignedPreKey(OmemoDevice userDevice, int signedPreKeyId, T_SigPreKey signedPreKey) throws IOException;
 
     /**
      * Remove a signedPreKey from storage.
@@ -482,8 +508,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @param contactsDevice device whose session we want to load
      * @return crypto related session
+     * @throws IOException
      */
-    public abstract T_Sess loadRawSession(OmemoDevice userDevice, OmemoDevice contactsDevice);
+    public abstract T_Sess loadRawSession(OmemoDevice userDevice, OmemoDevice contactsDevice) throws IOException;
 
     /**
      * Load all crypto-lib specific session objects of contact 'contact'.
@@ -491,8 +518,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @param contact BareJid of the contact we want to get all sessions from
      * @return TreeMap of deviceId and sessions of the contact
+     * @throws IOException
      */
-    public abstract HashMap<Integer, T_Sess> loadAllRawSessionsOf(OmemoDevice userDevice, BareJid contact);
+    public abstract HashMap<Integer, T_Sess> loadAllRawSessionsOf(OmemoDevice userDevice, BareJid contact) throws IOException;
 
     /**
      * Store a crypto-lib specific session to storage.
@@ -500,8 +528,9 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @param contactsDevice  OmemoDevice whose session we want to store
      * @param session session
+     * @throws IOException
      */
-    public abstract void storeRawSession(OmemoDevice userDevice, OmemoDevice contactsDevice, T_Sess session);
+    public abstract void storeRawSession(OmemoDevice userDevice, OmemoDevice contactsDevice, T_Sess session) throws IOException;
 
     /**
      * Remove a crypto-lib specific session from storage.
@@ -535,15 +564,17 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @param contact contact we want to get the deviceList of
      * @return CachedDeviceList of the contact
+     * @throws IOException
      */
-    public abstract OmemoCachedDeviceList loadCachedDeviceList(OmemoDevice userDevice, BareJid contact);
+    public abstract OmemoCachedDeviceList loadCachedDeviceList(OmemoDevice userDevice, BareJid contact) throws IOException;
 
     /**
      * Load a list of deviceIds from our own devices.
      * @param userDevice
      * @return
+     * @throws IOException
      */
-    public OmemoCachedDeviceList loadCachedDeviceList(OmemoDevice userDevice) {
+    public OmemoCachedDeviceList loadCachedDeviceList(OmemoDevice userDevice) throws IOException {
         return loadCachedDeviceList(userDevice, userDevice.getJid());
     }
 
@@ -554,10 +585,11 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @param userDevice our OmemoDevice.
      * @param contact    Contact
      * @param contactsDeviceList list of the contacts devices' ids.
+     * @throws IOException
      */
     public abstract void storeCachedDeviceList(OmemoDevice userDevice,
                                                BareJid contact,
-                                               OmemoCachedDeviceList contactsDeviceList);
+                                               OmemoCachedDeviceList contactsDeviceList) throws IOException;
 
     /**
      * Delete this device's IdentityKey, PreKeys, SignedPreKeys and Sessions.
@@ -580,9 +612,10 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @return fingerprint of our identityKeyPair
      *
      * @throws CorruptedOmemoKeyException if the identityKey of userDevice is corrupted.
+     * @throws IOException
      */
     public OmemoFingerprint getFingerprint(OmemoDevice userDevice)
-            throws CorruptedOmemoKeyException {
+            throws CorruptedOmemoKeyException, IOException {
 
         T_IdKeyPair keyPair = loadOmemoIdentityKeyPair(userDevice);
         if (keyPair == null) {
@@ -600,9 +633,10 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @return fingerprint of the userDevices IdentityKey.
      * @throws CorruptedOmemoKeyException if the IdentityKey is corrupted.
      * @throws NoIdentityKeyException if no IdentityKey for contactsDevice has been found locally.
+     * @throws IOException
      */
     public OmemoFingerprint getFingerprint(OmemoDevice userDevice, OmemoDevice contactsDevice)
-            throws CorruptedOmemoKeyException, NoIdentityKeyException {
+            throws CorruptedOmemoKeyException, NoIdentityKeyException, IOException {
 
         T_IdKey identityKey = loadOmemoIdentityKey(userDevice, contactsDevice);
         if (identityKey == null) {
@@ -625,10 +659,11 @@ public abstract class OmemoStore<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @throws SmackException.NotConnectedException
      * @throws InterruptedException
      * @throws SmackException.NoResponseException
+     * @throws IOException
      */
     public OmemoFingerprint getFingerprintAndMaybeBuildSession(OmemoManager.LoggedInOmemoManager managerGuard, OmemoDevice contactsDevice)
             throws CannotEstablishOmemoSessionException, CorruptedOmemoKeyException,
-            SmackException.NotConnectedException, InterruptedException, SmackException.NoResponseException {
+            SmackException.NotConnectedException, InterruptedException, SmackException.NoResponseException, IOException {
         OmemoManager omemoManager = managerGuard.get();
 
         // Load identityKey
diff --git a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/internal/listener/OmemoCarbonCopyStanzaReceivedListener.java b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/internal/listener/OmemoCarbonCopyStanzaReceivedListener.java
index 4d766025c..cdfc31389 100644
--- a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/internal/listener/OmemoCarbonCopyStanzaReceivedListener.java
+++ b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/internal/listener/OmemoCarbonCopyStanzaReceivedListener.java
@@ -16,6 +16,8 @@
  */
 package org.jivesoftware.smackx.omemo.internal.listener;
 
+import java.io.IOException;
+
 import org.jivesoftware.smack.packet.Message;
 
 import org.jivesoftware.smackx.carbons.packet.CarbonExtension;
@@ -26,5 +28,6 @@ import org.jivesoftware.smackx.omemo.OmemoManager;
  */
 public interface OmemoCarbonCopyStanzaReceivedListener {
 
-    void onOmemoCarbonCopyReceived(CarbonExtension.Direction direction, Message carbonCopy, Message wrappingMessage, OmemoManager.LoggedInOmemoManager omemoManager);
+    void onOmemoCarbonCopyReceived(CarbonExtension.Direction direction, Message carbonCopy, Message wrappingMessage,
+                    OmemoManager.LoggedInOmemoManager omemoManager) throws IOException;
 }
diff --git a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/internal/listener/OmemoMessageStanzaReceivedListener.java b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/internal/listener/OmemoMessageStanzaReceivedListener.java
index 031f259d8..c6d7ecc58 100644
--- a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/internal/listener/OmemoMessageStanzaReceivedListener.java
+++ b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/internal/listener/OmemoMessageStanzaReceivedListener.java
@@ -16,11 +16,13 @@
  */
 package org.jivesoftware.smackx.omemo.internal.listener;
 
+import java.io.IOException;
+
 import org.jivesoftware.smack.packet.Stanza;
 
 import org.jivesoftware.smackx.omemo.OmemoManager;
 
 public interface OmemoMessageStanzaReceivedListener {
 
-    void onOmemoMessageStanzaReceived(Stanza stanza, OmemoManager.LoggedInOmemoManager omemoManager);
+    void onOmemoMessageStanzaReceived(Stanza stanza, OmemoManager.LoggedInOmemoManager omemoManager) throws IOException;
 }
diff --git a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/util/OmemoMessageBuilder.java b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/util/OmemoMessageBuilder.java
index 197aab42d..043d6a32b 100644
--- a/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/util/OmemoMessageBuilder.java
+++ b/smack-omemo/src/main/java/org/jivesoftware/smackx/omemo/util/OmemoMessageBuilder.java
@@ -20,6 +20,7 @@ import static org.jivesoftware.smackx.omemo.util.OmemoConstants.Crypto.CIPHERMOD
 import static org.jivesoftware.smackx.omemo.util.OmemoConstants.Crypto.KEYLENGTH;
 import static org.jivesoftware.smackx.omemo.util.OmemoConstants.Crypto.KEYTYPE;
 
+import java.io.IOException;
 import java.io.UnsupportedEncodingException;
 import java.nio.charset.StandardCharsets;
 import java.security.InvalidAlgorithmParameterException;
@@ -219,10 +220,11 @@ public class OmemoMessageBuilder<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey, T_
      * @throws CorruptedOmemoKeyException if the identityKey of that device is corrupted.
      * @throws UndecidedOmemoIdentityException if the user hasn't yet decided whether to trust that device or not.
      * @throws UntrustedOmemoIdentityException if the user has decided not to trust that device.
+     * @throws IOException
      */
     public void addRecipient(OmemoDevice contactsDevice)
             throws NoIdentityKeyException, CorruptedOmemoKeyException, UndecidedOmemoIdentityException,
-            UntrustedOmemoIdentityException {
+            UntrustedOmemoIdentityException, IOException {
 
         OmemoFingerprint fingerprint;
         fingerprint = OmemoService.getInstance().getOmemoStoreBackend().getFingerprint(userDevice, contactsDevice);
diff --git a/smack-omemo/src/test/java/org/jivesoftware/smackx/omemo/OmemoStoreTest.java b/smack-omemo/src/test/java/org/jivesoftware/smackx/omemo/OmemoStoreTest.java
index 369c682d9..96b9be7fc 100644
--- a/smack-omemo/src/test/java/org/jivesoftware/smackx/omemo/OmemoStoreTest.java
+++ b/smack-omemo/src/test/java/org/jivesoftware/smackx/omemo/OmemoStoreTest.java
@@ -302,20 +302,20 @@ public abstract class OmemoStoreTest<T_IdKeyPair, T_IdKey, T_PreKey, T_SigPreKey
     }
 
     @Test
-    public void loadAllRawSessionsReturnsEmptyMapTest() {
+    public void loadAllRawSessionsReturnsEmptyMapTest() throws IOException {
         HashMap<Integer, T_Sess> sessions = store.loadAllRawSessionsOf(alice, bob.getJid());
         assertNotNull(sessions);
         assertEquals(0, sessions.size());
     }
 
     @Test
-    public void loadNonExistentRawSessionReturnsNullTest() {
+    public void loadNonExistentRawSessionReturnsNullTest() throws IOException {
         T_Sess session = store.loadRawSession(alice, bob);
         assertNull(session);
     }
 
     @Test
-    public void loadStoreMessageCounterTest() {
+    public void loadStoreMessageCounterTest() throws IOException {
         assertEquals(0, store.loadOmemoMessageCounter(alice, bob));
         store.storeOmemoMessageCounter(alice, bob, 20);
         assertEquals(20, store.loadOmemoMessageCounter(alice, bob));