diff --git a/NetTunnelSDK/UserManager.cpp b/NetTunnelSDK/UserManager.cpp
index f66e933..410b1f7 100644
--- a/NetTunnelSDK/UserManager.cpp
+++ b/NetTunnelSDK/UserManager.cpp
@@ -474,6 +474,7 @@ int GetUserClientConfigure(const TCHAR *pUserName, const TCHAR *pToken, PUSER_CL
     PUSER_CLIENT_CONFIG pUserCfg = &pUser->cliConfig;
     TCHAR               userPath[MAX_PATH];
     int                 ret;
+    TCHAR              *pConvRet;
 
 #if USER_REAL_PLATFORM
     ProtocolRequest<ReqGetUserCfgParams>    req;
@@ -565,9 +566,9 @@ int GetUserClientConfigure(const TCHAR *pUserName, const TCHAR *pToken, PUSER_CL
         return ret;
     }
 
-    ret = strtol(rsp.code.c_str(), nullptr, 10);
+    ret = strtol(rsp.code.c_str(), &pConvRet, 10);
 
-    if (ret != 0) {
+    if (ret != 0 || lstrlen(pConvRet) > 0) {
         SPDLOG_ERROR(TEXT("Server response error code: {0}"), ret);
         return -ERR_HTTP_SERVER_RSP;
     }