Never an easy problem to solve- could be anything from conflicting or out of date drivers, processor overheating, overdemand on system resources and God knows what else. There's a useful site here that should enable you to check out the error message and narrow down the possibilities. Also, and I hope I'm not upsetting anyone by referring to another forum, but subscribe here and you should get some useful feedback. I've had a similar problem recently, which turned out to be two conflicting intellimouse driver versions fighting for supremecy. Good luck, but persevere!