Intelliadmin published this earlier today… with all the problems some people have had with the Genuine advantage notification that their copy of Windows may not be legitimate (many reasons for this…) it may be necessary to buy a new copy of Windows and it would be a nuisance to have to reinstall. So, there is a way to just update the serial number to the new copy. The download from Microsoft can be found here and checks the main system files (for patching/changes to circumvent WGA) and then asks for the new Product Key. Reboot and it should have updated the serial number and maybe WGA will let you do updates.