Are you using Windows 7 RC 7100 evaluation? be informed, this evaluation would expire within a short time. I received a notification around 12 hours back that my copy would expire within 7 days and CLEARLY asked me to take a backup of the stuff I have with this instance!

So be ready, if you were ‘enjoying’ the free copy of Windows7 evaluation, RC 7100 you should hurry up to make backups and plan for a clean installation. There are numerous work arounds posted over internet about an upgrade from RC to a full version of Microsoft Windows 7 ultimate edition (ie, you cannot upgrade your copy of free ultimate evaluation copy to Windows 7 professional, enterprise or home premium editions)

If you are curious to know how it works, please follow this link