Windows Activation Technoligies

Windows Genuine Advantage (WGA) is an anti-piracy system created by Microsoft that enforces online validation of the licensing of several recent Windows OS when accessing several services, such as Windows Update, and downloading Windows components from the Microsoft Download Center.
In Windows 7 this was renamed to Windows Activation Technology (WAT). WGA consists of two components: an installable component called WGA Notifications that hooks into Winlogin and validates the Windows license upon each logon and an ActiveX control that checks the validity of the Windows license when downloading certain updates from the Microsoft Download Center or windows update.
When the validity of your license is called into question  by WAT you will continually be reminded that your software is not genuine and you may be a victim of fraud. Also what ever wallpaper you had displayed will be replaced by a black screen. Your computer performance will still be intact but u will no longer have access to new Windows updates.
Some people consider this 'Time Bomb Software' and as such Windows Vista has reduced WGA to the nag-only method of WinXP as opposed to the compromised functionality of other releases...
I recently became a victim of this Software harassment when I launched a series of updates that included IE9 and Windows 7 SP1. Once I realized what was happening to my system, I promptly uninstalled IE9 and the updated Windows Activation Checker (KB971033). This unfortunately did not fix the problem so I had to resort to using my 'RemoveWAT 2.2.7' utility to eliminate this nuisance. Although I had used this tool before to eliminate the WAT, the trick was to restore it first, re-boot and then remove it again. I used this method on two of my system with great success.
If you are not tech savvy enough to maneuver around such annoyances then I highly encourage you to activate your windows through Microsoft by buying it.

RPM