Problem with back button in browser

Hi!

I installed my web application on Windows 2003 Server and when I use
back button in browser, then do something on page (which causes
postback), I get 'Sys.WebForms.PageRequestManagerServerErrorException:
An unknown error occurred while processing the request on the server.
The status code returned from the server was: 500' error. I don't get
this error when I install application on Windows XP. This is propably a
matter of settings, but I can't find them. What can be the reason?

--
Lukasz Ledochowski
GG: 503647