Office 2007 apps crash on close

I seem to have a problem with Office 2007 SP2 apps crashing on close (both document and app close) with NIS 17.0.0.136 installed. The same installation did not have this problem with Avira AntiVir; no other (driver or otherwise) changes have been made but completely removing Avira and installing NIS; no previous Norton product was installed. NIS is the only security product installed. No other MDI apps seem to have this problem; turning the Microsoft Office Automatic Scan on or off makes no difference.

 

Does anyone else see this problem?

 

OS: Windows 7 x64 RTM

Keyboard and mouse driver: Logitech Setpoint 4.80.