Recently, I've ran into a problem regarding the Hamachi network driver which just wouldn't install. I thought it was a hamachi specific problem but turns out I can't install any other driver either, I've tried updating my video drivers, sound card drivers and network adapter drivers, all of which fails, but the older drivers were removed. I had to boot into safe mode in order to be able to install these drivers. Also, I've desactivated my antivirus thinking it had something to do with the hamachi problem, and now I just can't enable it again.
Maybe it's some kind of virus? I don't have the option to format this PC, because my windows 7 instalation disc is miles away and this internet connection is too slow.