Just a quick question...how long after it requests a scan does it log off? Also try http://www.kaspersky.com/virusscanner let is scan your computer. In addition to viruses, your computer may be infected with spywares, Trojans, worms, adwares, viruses and other malwares. Also, I do recommend that you clean/restore your registry files…if these are corrupted, your PC will slow down and have startup problems.