CGI Error

[smtest]

hi,
i am trying to do a stress testing with few hundred users (running report at one time). I get this error:
"The specified CGI application misbehaved by not returning a complete set of HTTP headers"
Cognos suggested me to create a new application pool called crn. Because of the load, the default application tool maybe shared by some other applications running on the server. But there is nothing else except cognos services on that particular server
pls advice