diff --git a/include/TNetwork.h b/include/TNetwork.h
index 9f55df6..1640be6 100644
--- a/include/TNetwork.h
+++ b/include/TNetwork.h
@@ -55,6 +55,7 @@ private:
     TResourceManager& mResourceManager;
     std::thread mUDPThread;
     std::thread mTCPThread;
+    std::mutex mOpenIDMutex;
 
     std::vector<uint8_t> UDPRcvFromClient(ip::udp::endpoint& ClientEndpoint);
     void HandleDownload(TConnection&& TCPSock);
diff --git a/src/TNetwork.cpp b/src/TNetwork.cpp
index 1d8d0e5..9b17bce 100644
--- a/src/TNetwork.cpp
+++ b/src/TNetwork.cpp
@@ -630,6 +630,7 @@ void TNetwork::OnDisconnect(const std::weak_ptr<TClient>& ClientPtr) {
 }
 
 int TNetwork::OpenID() {
+    std::unique_lock OpenIDLock(mOpenIDMutex);
     int ID = 0;
     bool found;
     do {