4 Replies Latest reply: Dec 28, 2017 12:02 PM by Peter Cammaert RSS

    Failed to listen on prefix http://*:4780/QEMC/ because it conflicts with an existing registration on the machine

    German Etcheverry

      Hello everyone,


      I am upgrading from Qlikview 12.0 to 12.20,
      After upgrading I get the error below (I am unable to access my QMC)


      Failed to start QMS web server on port 4780. Exception : System.Net.HttpListenerException (0x80004005): Failed to listen on prefix 'http://*:4780/QEMC/' because it conflicts with an existing registration on the machine. ||    at System.Net.HttpListener.AddAllPrefixes() ||    at System.Net.HttpListener.Start() ||    at QMS.BackstageWebServer.RegisterWebserverPrefixesAndStart(Int32 iPort, String scheme)


      Failed to start frontend web server. System.ObjectDisposedException: Cannot access a disposed object. || Object name: 'System.Net.HttpListener'. ||    at System.Net.HttpListener.BeginGetContext(AsyncCallback callback, Object state) ||    at QMS.MainLoop.StartupWebServer(Action`1 webServerTracer)


      Fail Connect to: server Error:No connection could be made because the target machine actively refused it IP ADDRESS:4747

      This is causing the QMS service to fail. I have checked the server binding (no duplicates) , I have restarted the server, IIS application pool is online, IIS services are online as well (though in the past it wasn't, it said: IIS wont start- another website may be using the same port), Qlikview services work except for the QMS service (because of the port issue), have done a netstat -a to check all the ports (and noticed the website port for the QMC site has been removed but not sure how to get this back).