I note that a few of the PCs that I support have had their Automatic Updates turned back on to fully automatic recently. They were then hit again with the nonsensical WGA (Windows Genuine DISAdvantage) tool that incorrectly declares that the PC in question has non-genuine software installed.
Now I know this to be false, and have been able to remove this heinous piece of nagware from the PCs, only to find out it gets installed again. Automagically - good old Microsoft.
So a word of advice - if you do need to use the removewga.exe tool, first check that Automatic Updates aren't set to full autopilot or you will end up going round and round in circles.