I am running XP Pro (SP2) and I haven't installed any new software programs except a few weeks ago I purchased and installed the upgrade version of Acrobat 7. I also installed an extra 512MB RAM at about the same time (RAM was purchased through Dell and was compatible) I have had this computer since 2/2003 and have had absolutely no problems whatsoever for the entire time.
On Friday I couldn't shut down and I haven't been able to shut down since. I ran a virus scan and I ran 2 malware scans using Spybot and Ad-aware, which have served me quite well. The virus scan was clean and the malware scans found few problems. I really feel I may have been invaded by a Trojan(?)
I appreciate anything you can advise. Thanks.