I am using Qt5 on windows7. I have desktop application which is server/client kind of application. Application calls http request and get data from server. My application has polling mechanism which calls one http method to check server is available or not. It does this every 5 second. Now issue is when in midnight server gets restarted my application goes offline and then come online mode. In this case after few hours I get error message "Fatal:Qt: INTERNALL ERROR: failed to install GetMessage hook". I am not sure why this error comes and there is no detail on that. I am using qDebug to print logs and I found above error information from that log. Let me know if anyone has idea about this error.