HEY You may be a victim of software counterfeiting!
OMFG... I have a log server (running Kiwi of course) that was an OEM Dell NT workstation with licensed copy and was upgraded to XP Pro with a corporate license that I personally bought and intalled. This thing has been running for years along winodows update and that annoying Windows Genuine Advantage tool for months. Today... Your Copy of WIndows is not genuine. Absolutely no changes to any configuration. Ok fine...
Del *.*
Format C:
boot : Linux install
FLUSH whats that? The sound of another windows box going into the toilet.