diff --git a/src/iec61850/inc_private/ied_server_private.h b/src/iec61850/inc_private/ied_server_private.h
index 43ffb56c..e51a48ed 100644
--- a/src/iec61850/inc_private/ied_server_private.h
+++ b/src/iec61850/inc_private/ied_server_private.h
@@ -95,6 +95,9 @@ private_IedServer_getClientConnectionByHandle(IedServer self, void* serverConnec
 LIB61850_INTERNAL ClientConnection
 private_ClientConnection_create(void* serverConnectionHandle);
 
+LIB61850_INTERNAL void
+private_ClientConnection_invalidate(ClientConnection self);
+
 LIB61850_INTERNAL int
 private_ClientConnection_getTasksCount(ClientConnection self);
 
diff --git a/src/iec61850/server/impl/client_connection.c b/src/iec61850/server/impl/client_connection.c
index d8a76a21..e8a6e2de 100644
--- a/src/iec61850/server/impl/client_connection.c
+++ b/src/iec61850/server/impl/client_connection.c
@@ -57,6 +57,20 @@ struct sClientConnection
 #endif /* _TLS_OWN_CNT_SEM */
 };
 
+void
+private_ClientConnection_invalidate(ClientConnection self)
+{
+#if (CONFIG_MMS_THREADLESS_STACK != 1)
+    Semaphore_wait(self->accessMutex);
+#endif
+
+    self->serverConnectionHandle = NULL;
+
+#if (CONFIG_MMS_THREADLESS_STACK != 1)
+    Semaphore_post(self->accessMutex);
+#endif
+}
+
 ClientConnection
 private_ClientConnection_create(void* serverConnectionHandle)
 {
diff --git a/src/iec61850/server/mms_mapping/mms_mapping.c b/src/iec61850/server/mms_mapping/mms_mapping.c
index 7e09ed28..e5e6b034 100644
--- a/src/iec61850/server/mms_mapping/mms_mapping.c
+++ b/src/iec61850/server/mms_mapping/mms_mapping.c
@@ -3354,6 +3354,8 @@ mmsConnectionHandler(void* parameter, MmsServerConnection connection, MmsServerE
         unselectAllSettingGroups(self, connection);
 #endif
 
+        private_ClientConnection_invalidate(clientConnection);
+
         ClientConnection_release(clientConnection);
     }
     else if (event == MMS_SERVER_NEW_CONNECTION) {
diff --git a/src/mms/iso_mms/server/mms_server_connection.c b/src/mms/iso_mms/server/mms_server_connection.c
index d8c1b657..644fcdb1 100644
--- a/src/mms/iso_mms/server/mms_server_connection.c
+++ b/src/mms/iso_mms/server/mms_server_connection.c
@@ -818,7 +818,6 @@ MmsServerConnection_init(MmsServerConnection connection, MmsServer server, IsoCo
 void
 MmsServerConnection_destroy(MmsServerConnection self)
 {
-
 #if (MMS_FILE_SERVICE == 1)
     int frsmIndex = 0;