Office 2007 save as pdf fails

Every time I try to save a document as pdf in Windows 7, Office 2007 fails .It says " Failed to export file to pdf due to unknown error." I have the latest updates for Office 2007 SP2 and tried setting permissions, saving to different folders. how can i do?
You can get this tool( 2007 Microsoft Office Add-in: Microsoft Save as PDF or XPS ) at the link:
Office 2007 will Work like a charm.

Helo, It turns out it was Kaspersky antivirus beta. When I disabled Kaspersky, it worked fine.
But I have yet to find out how to make it work without disabling Kaspersky.