I have an ASP.NET app with crystal reports. The problem I'm having is that when one user clicks the button

I've supplied for exporting the report to PDF all he gets is a blank page. If he then clicks the Back button

on the browser, Acrobat Reader lauchhes and kicks out the following error:

File does not begin with %PDF-

Naturally, it works fine on every one elses machines. I've compared IE versions, Acrobat versions, tried

different versions of Acrobat Reader, and several other things.

Any ideas anyone?