I understand (though I didn't experience any of this myself, since I have update turned OFF) that Microsoft recently released a series of critical patches. So critical were they that homeland security was urging everyone to get their computers updated IMMEDIATELY .......... and I guess most did!~
This (seemingly) overloaded Microsoft servers and many people were left hanging (literally) when their updates wouldn't work.
Now, I'm thinking that possibly the "genuine advantage" check tool got mixed in with all of this somehow and caused all kinds of errors to compile on top of the other ones.
Just a guess though. You may have got caught with the tool and then later Microsoft turned it off. ??