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

[Anonymous]

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).

[Peter_Cammaert]

If you stop IIS, are you then able to start the QMS service?

The error messages point in all directions. .Net installation broken (which version of .Net is installed on your platform)? Firewall blocking port 4747 (but that shouldn't impact the QMS)? QEMC?

[Anonymous]

If you stop IIS, are you then able to start the QMS service?

I stopped IIS and noticed I can start the QMS service with no issue now. QMC still doesnt work but this is a good test. Do you have any other suggestions? When I start the IIS (while the QMS service is running...)I get a pop up saying "The website cannot be started. Another website maybe using the same port".

The error messages point in all directions. .Net installation broken (which version of .Net is installed on your platform)? Firewall blocking port 4747 (but that shouldn't impact the QMS)? QEMC?

You are saying my .Net Installation is broken? I am on 4.5.2. Port 4747 is for Qlikview Server. QMS is for 4780.

[Peter_Cammaert]

1. Apparently there is a conflcit between IIS and QMS fighting for control of the same port. And the same url. Check your IIS configuration. Which web sites are defined and to which ports are they bound? Has the default web site (or the site that QlikView is appearing on) made a binding to port 4780?
2. I just remarked that the three different error messages all point in different directions (and gave you an explanation of what they *might* mean). The most common causes of problems like those three messages apparently indicate may have nothing to do with your situation, but that's all information we're getting at the moment. Let's assume that they'll disappear once we fix the port conflict.

[Peter_Cammaert]

Remember that IIS has nothing to do with the QMC. The QlikView Management Service has an own web server that displays the Management Console and that cannot be replaced by some web server that is more to your liking.