Product:
Cognos Controller 10.1

Symptom:
Error before login to Cognos Controller you get an error message. You get the message after you have selected the controller database to use.

Error message:
Log On IBM Cognos Controller

AAA-AUT-0011
Invalid namespace was selected

Cause:
Cognos Controller 10 is setup to talk to a Cognos BI 8 installation.

The Dispatcher URI in Controller Configuration Report Server is not only used when you run the standard reports – it is also used when validate the login when using Server Authentication. The Report Server Dispatcher value is inherited to Server Authentication.

The values for Report Server will be reset to default values when you install the Cognos Controller Update Components Fix Pack on a existing Cognos Controller installation.
https://www-304.ibm.com/support/docview.wss?uid=swg27020782

Solution:
On the Cognos Controller application server
Start IBM Cognos Controller Configuration
Select Report Server in the list
Change the Dispatcher URI to be a valid URL

To something like this
http://SRV001:9300/p2pd/servlet/dispatch

Click Save
Exit Controller Configuration
Start Cognos Controller client and test again.

More Information:
If the Cognos BI service is not available you will get an error of this kind instead:
IBM Cognos Business Intelligence
Error executing request. Please verify that the target URI is valid and that IBM Cognos is online.

Below error message in Swedish:

”IBM Cognos-gatewayen kan inte ansluta till IBM Cognos BI-servern. Servern kan vara otillgänglig eller så kan gatewayen vara felaktigt konfigurerad.”
”Försök igen eller kontakta administratören.”