Since about a week my PC with XP (SP3) has become very unstable and crashes now and then.
I don't know if it is related, but I think it occurred after the installation of the critical MS update, combined with the .net framework SP1. I uninstalled both, but that did not work.
I also did the Trend Micro housecall and checked with HijackThis, but no viruses/malware etc.
What can I do more to find and solve this problem?
BTW, also Firefox crashes often, can there be a relation?

