Product:
Cognos Controller 10.1
Microsoft Windows 2008 R2

Symptom:
The Cognos Controller client freeze (hang) after you have selected the database to use. The login dialog is not showing up. There are no error messages in windows event log.

If you run Controller Client direct on the Controller Application server – it works fine.
But from all client computers the Controller Client will hang.

Problem:
When Cognos Controller client start it will contact Cognos connection to check if it is there, even if you use native controller security. When report server setting is http://localhost/ibmcognos/cgi-bin/cognosisapi.dll , this will not work – Cognos connection can not be found on the local client.

You can sometimes get a Internet Explorer 404 error in Controller before the login dialog.

Cause:
After you have applied the Cognos Controller hot fix, the settings in Controller configuration is reverted back to default values. Therefore the Report server value is localhost and not the server name.

Solution:
Open Controller Configuration on your Controller server.
Go to the Report Server tab.
Change the url from localhost to the servername

Report server should be:
http://srv001/ibmcognos/cgi-bin/cognosisapi.dll

Dispatcher URI should be:
http://srv001:9300/p2pd/servlet/dispatch

(change srv001 to your server name)

Click save and close.
Test again.