diff --git a/lib/tunnelbroker/use-peer-to-peer-message-handler.js b/lib/tunnelbroker/use-peer-to-peer-message-handler.js
--- a/lib/tunnelbroker/use-peer-to-peer-message-handler.js
+++ b/lib/tunnelbroker/use-peer-to-peer-message-handler.js
@@ -41,7 +41,7 @@
 import { getMessageForException } from '../utils/errors.js';
 import {
   hasHigherDeviceID,
-  OLM_SESSION_ERROR_PREFIX,
+  OLM_ERROR_FLAG,
   olmSessionErrors,
 } from '../utils/olm-utils.js';
 import { getClientMessageIDFromTunnelbrokerMessageID } from '../utils/peer-to-peer-communication-utils.js';
@@ -304,10 +304,7 @@
               `${message.senderInfo.deviceID}: ${e.message}`,
           );
 
-          if (
-            !e.message?.includes(OLM_SESSION_ERROR_PREFIX) &&
-            !e.message?.includes(olmSessionErrors.sessionDoesNotExist)
-          ) {
+          if (!e.message?.includes(OLM_ERROR_FLAG)) {
             throw e;
           }
 
diff --git a/lib/utils/olm-utils.js b/lib/utils/olm-utils.js
--- a/lib/utils/olm-utils.js
+++ b/lib/utils/olm-utils.js
@@ -104,6 +104,11 @@
 }
 
 export const OLM_SESSION_ERROR_PREFIX = 'OLM_';
+
+// this constant has to match olmErrorFlag constant
+// in native/cpp/CommonCpp/CryptoTools/Session.h
+export const OLM_ERROR_FLAG = 'OLM_ERROR';
+
 const olmSessionErrors = Object.freeze({
   // Two clients send the session request to each other at the same time,
   // we choose which session to keep based on `deviceID`.
diff --git a/native/cpp/CommonCpp/CryptoTools/Session.h b/native/cpp/CommonCpp/CryptoTools/Session.h
--- a/native/cpp/CommonCpp/CryptoTools/Session.h
+++ b/native/cpp/CommonCpp/CryptoTools/Session.h
@@ -15,6 +15,10 @@
   OlmBuffer olmSessionBuffer;
   int version;
 
+  // this constant has to match OLM_ERROR_FLAG constant in
+  // lib/utils/olm-utils.js
+  const std::string olmErrorFlag = "OLM_ERROR";
+
 public:
   static std::unique_ptr<Session> createSessionAsInitializer(
       OlmAccount *account,
diff --git a/native/cpp/CommonCpp/CryptoTools/Session.cpp b/native/cpp/CommonCpp/CryptoTools/Session.cpp
--- a/native/cpp/CommonCpp/CryptoTools/Session.cpp
+++ b/native/cpp/CommonCpp/CryptoTools/Session.cpp
@@ -174,8 +174,8 @@
       decryptedMessage.size());
   if (decryptedSize == -1) {
     throw std::runtime_error{
-        "error decrypt => " + std::string{::olm_session_last_error(session)} +
-        ". Hash: " +
+        "error decrypt => " + olmErrorFlag + " " +
+        std::string{::olm_session_last_error(session)} + ". Hash: " +
         std::string{messageHashBuffer.begin(), messageHashBuffer.end()}};
   }
   return std::string{(char *)decryptedMessage.data(), decryptedSize};
diff --git a/web/shared-worker/worker/worker-crypto.js b/web/shared-worker/worker/worker-crypto.js
--- a/web/shared-worker/worker/worker-crypto.js
+++ b/web/shared-worker/worker/worker-crypto.js
@@ -31,6 +31,7 @@
   shouldForgetPrekey,
   shouldRotatePrekey,
   olmSessionErrors,
+  OLM_ERROR_FLAG,
 } from 'lib/utils/olm-utils.js';
 
 import { getIdentityClient } from './identity-client.js';
@@ -611,10 +612,15 @@
       throw new Error(olmSessionErrors.invalidSessionVersion);
     }
 
-    const result = olmSession.session.decrypt(
-      encryptedData.messageType,
-      encryptedData.message,
-    );
+    let result;
+    try {
+      result = olmSession.session.decrypt(
+        encryptedData.messageType,
+        encryptedData.message,
+      );
+    } catch (e) {
+      throw new Error(`error decrypt => ${OLM_ERROR_FLAG} ` + e.message);
+    }
 
     await persistCryptoStore();
 
@@ -642,10 +648,15 @@
       throw new Error(olmSessionErrors.invalidSessionVersion);
     }
 
-    const result = olmSession.session.decrypt(
-      encryptedData.messageType,
-      encryptedData.message,
-    );
+    let result;
+    try {
+      result = olmSession.session.decrypt(
+        encryptedData.messageType,
+        encryptedData.message,
+      );
+    } catch (e) {
+      throw new Error(`error decrypt => ${OLM_ERROR_FLAG} ` + e.message);
+    }
 
     const sqliteQueryExecutor = getSQLiteQueryExecutor();
     const dbModule = getDBModule();
@@ -703,10 +714,15 @@
     );
 
     contentAccount.remove_one_time_keys(session);
-    const initialEncryptedMessage = session.decrypt(
-      initialEncryptedData.messageType,
-      initialEncryptedData.message,
-    );
+    let initialEncryptedMessage;
+    try {
+      initialEncryptedMessage = session.decrypt(
+        initialEncryptedData.messageType,
+        initialEncryptedData.message,
+      );
+    } catch (e) {
+      throw new Error(`error decrypt => ${OLM_ERROR_FLAG} ` + e.message);
+    }
 
     contentSessions[contentIdentityKeys.ed25519] = {
       session,