Give some more details on the errors you are getting. But some good starts would be:
Antivirus: (AVG) http://free.grisoft.com/doc/2/
AntiSpy/Malware (Windows Defender): http://www.microsoft.com/athome/security…
Once you do full updates and scans with those 2 things… and you’re still getting errors… repost a question with the exact errors.