"Index was out of range ... Parameter name: startIndex" when launching Controller client, caused by incorrect IIS settings on application server

Technote (troubleshooting)


User launches Controller client. User receives error message.



An Error occurred while trying to access the server.
[Details] [OK]

Error Details
Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: startIndex


There are several possible causes for this error message.

  • TIP: See separate IBM Technote #1669496 for more examples.

This Technote specifically relates to the scenario where the cause is that the Controller application server does not contain the required IIS virtual directories (in order to process requests from the client).
  • Specifically, it is caused by 'ibmcognos\controllerserver' being missing (or invalid).

Resolving the problem

Ensure that the Controller application server contains the correct IIS virtual directories/applications in its website, such as:

  • ibmcognos
  • ibmcognos\cgi-bin
  • ibmcognos\controller
  • ibmcognos\controllerbin
  • ibmcognos\controllerhelp
  • ibmcognos\controllerserver

TIP: The ones highlighted in bold are the most relevant directories for this issue.

Related information

1669496 - ** Troubleshooting ** "Index was out of range

Document information

More support for:

Cognos Controller

Software version:


Operating system(s):


Reference #:


Modified date:


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