Crystal Reports 8 User session expired error

Hi,
As we are migrating from NT server to Win 2003 server. web applications are moved over from nt as well. I am facing problem with one the web apps which uses crystal reports 8. "User Session expired" error msg is popping out when we try to export the report into any supported format such html, excel, word etc.. The report comes up no issues..however unable to use export option.

I went through the business objects .pdf for user session expired err msg...but nothing helped. i am still stuck with this problem.
can anybody help me here pls.

FYI...It's a ASP/VB web appl using crystal reports 8.0 on Win 2003 machine.

thanks
DRM.Hello,

Further to my earlier msg, after commenting out the default error msg "User Session expired" i got this error msg

"The Report was not Exported. The selected report format may be disabled on the server" actually this is common msg coming up for all export formats...available in crystal 8.0 version.

Therefore, any ideas how to check/verify and Enable/Disable this on server?

ur help on this will be greatly appreciated.

thanks a ton in adv.

Cheers,
muki