I had installed ESET Smart Security (all updated) and it was working fine. Some time ago I checked an exe for viruses and it came out clean. But, on running it, I saw the waiting hourglass, then nothing. Then many executables (with names like "b.exe") appeared all over (C:, D:, in archives even). I've tried opening NOD32 but it wouldn't start (ekrn.exe was started but no UI appeared). (BTW, when in a browser, every site was working except for Eset.com, Kaspersky.com etc.). I've uninstalled NOD32, then tried reinstalling it. It wouldn't reinstall- at around 60% it said something like "can't access destination directory". I've noticed that that happens only (but always) when there is a virus. Then the computer became very slow and I was forced to reinstall Windows. Some questions: 1) I scanned the file by right-click> Scan for viruses. Is there other (better) way, since the first one was not efficient? 2) Why did NOD32 not appear when double-clicked? Because of the virus? 3) Is it possible for a virus to block certain internet sites? 4) Is it possible for a virus to block an anti-virus' installation? What could I do? 5) Any other ideas? (For Nr. 2) especially, because not being able to de-virus exactly when there IS a virus is very bad.) Thanks.