Well, malware could be the issue here. You could run a full scan with the two best freeware anti-malware scanners on the marked today. Run them one by one - full scan. Both can remove what they find:
Malwarebytes' Anti-Malware - download link: http://www.malwarebytes.org/mbam.php
SUPERAntiSpyware - download link: http://www.superantispyware.com/superantis...efreevspro.html
You should keep them. They really are the best that you can buy with no money at all.
Also these fine online scanners will do an excellent job - run one or two full scans. The ones mentioned above are better, though: http://www.bleepingcomputer.com/blogs/usas...?showentry=1252
Finally the free online Windows Live OneCare safety scanner automatically defragments your files. It also cleans up your registry, updates all Microsoft's programs and repair damaged Windows files. It is excellent but you do need to run at least two of the above mentioned anti-malware programs first. But give OneCare's defragment program a chance afterwards - go for a full scan. You won't regret it. This fine online scanner is grossly underestimated.
Edited by ePost, 04 January 2009 - 05:04 PM.