AVG is a pretty good program, so if it's saying you're clean you might not be updating it daily. If you do the daily updates, you probably have other issues. What makes you think it's a virus, it you anti-virus software shows up clean? You could try running a few anti-malware programs, like Spybot S&D, Ad-aware and System Care. There are a bunch of freeware apps on www.majorgeek.com that you can run a couple of times and do a couple of restarts, and see if that gets you anywhere. Then you can try a system restore without deleting your documents or settings. If that doesn't work, I would do what the post above says and get a new HD, install an OS on it, then add your current drive as a slave to pull your documents from. Then you will be free to format it and get back to where you want to be without losing too much, or wasting a bunch of time running your virus scan and wondering why it's still jacked up.