Ia m using Windows XP. My default web browser to visit website is Internet Explorer. I am not able to download virus definitions. It looks that my system has some kind of virus whic his redirecting me to some other site. I am trying go on AVG to download new updates, but the same failed. I also try to download other free antivirus manually but that does not worked. I need some help to deal with the issue. When I click on the download or try to open a site, I am getting a error that page not found. That is really weird.