Gears of War 2 is prone to a glitch that lets you boost your Xbox LIVE gamerscore by manipulating your profile. Unfortunately for those who have figured this out or looked it up online, Microsoft is well aware of the problem and is currently extracting vengeance on those who try to exploit it.
The hack – basically, swapping the profile on your Xbox storage with that of a player who has earned all the achievements – is a shortcut to lots of lovely, reputation-enhancing Gamerscore. As such, Microsoft has decided that the best response is to reset to zero the Gamerscore of anyone they find using the glitch.
As well as the pain of a rest Gamerscore, cheats will suffer the ignominy of being named & shamed via a “What happened to their Gamerscore? They’ve been caught cheating” Strap on their Xbox gamercard. Harsh, but fair.