Unable to start Controller Client 8.5

A user was promoting a new form within security groups and his PC crashed. He is now unable to login to the application but can login via Excel or another persons PC. The PC event log is attached. I have cleared local controller cache and our technical support have reviewed the .net. I have now asked for internet browser cache and cookies to be cleared.
I am unable to find any articles on this, similar ones exist for nullexception errors. We have logged this with IBM support, but their response is to check for locks without providing the table names.

I have checked all obvious table locks for the period and Forms but the user is not in the lock tables and the form is available to him via Excel and others generally.

The issue appears to be client PC based.

Any ideas

Click on the attachment to enlarge

Hi Bacchoi,

I have some additional questions for you:

  1. Are the PC’s real desktops?
  2. Is controller client installed on a CITRIX server? Or are the controller clients deployed on the PC of the controllers?
  3. What does the event log of the controller server say when this error occurs?

Please let me know, so i can help you further.

Yes the PC are real laptops not virtual
The controller client is deployed on the PC and is accessed using a desktop shortcut pointing to the server
I will ask the DBA for the event log of the controller server and post an update

Thanks for your interest


it looks client PC related if the same user can access controller from another PC.

On the pc there is a userprofile for controller

C:\Documents and Settings<username>\Application Data\Cognos\ccr directory
there are a lot of files and also a ccr.conf. these files were copied the when controller was opened the first time as that user. Maybe there is some corruption after the crash.


  1. close all controller related applications on the affected pc
  2. goto C:\Documents and Settings<username>\Application Data\Cognos\ccr
  3. delete or move ALL files and folders
  4. start controller again from this PC ie. http:///cognos8/controllerbin/ccr.exe
  5. Test if you can login now

good luck :slight_smile:

Just an update

IBM installed the CCR.exe and any other connection software locally on the users PC, this resolved the issue.
Previously the connection was a URL address to the Controller server located CCR.exe file.

We are monitoring all users for any re-occurance and will deploy the solution if encountered