NIS 2009 bluescreen!?

Hello

 

i got a problem with NIS 2009 when i'm not using the PC it all of a sudden makes a bluescreen and restarts automatically!?ca. every 10 min

I removed the whole NIS with you removing tool and tried with Zone alarm as Firewall and  Avira for Virus everything was ok. I installed NIS again and same happen again  bluescreen after and then every 10 min. Start using a screensaver so it doesn't happen anymore but today NIS wanted to make a full scan and the machine crashed.

Any good advise for me 

Thank you