This past weekend Microsoft's Windows Genuine Advantage server went down causing Windows Vista users to seen by Microsoft as pirated copies when they went to update their computers. One disadvantage to Microsoft's Windows Genuine Advantage DRM program--which forces Windows users to verify their software as "not-stolen" in order to receive certain patches and updates, including Internet Explorer 7--is that Microsoft's WGA server is not as highly reliable as Microsoft likes to advertise.
"When Microsoft's Windows Genuine Advantage server--presumably also running Windows--goes down, as it did this weekend, users attempting to verify their copy of Windows are automatically treated as counterfeiters and their Windows software goes into a “reduced functionality mode.” For Windows Vista users, that means the new Aero window appearance--Microsoft’s copy of Mac OS X’s Quartz--is turned off, reverting Vista Ultimate into plain old Windows XP."
Even XP users are affected by the WGA failure...