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#11
I think that what you are referring to is Clean My PC, which I have also. It is not a rogue, but I did have a situation like your's when I first started using W7. It listed far more problem keys than it should have, and despite the fact that I knew better, I went ahead and let it clean them.
I had to do a fresh install, but I have continued using that program since without incident. I have no idea of what happened, but apparently it can go quite haywire. That is why I now monitor what it wants to do very closely and I have it make a backup of the registry periodically.
When it works, it works well, and when it works badly, it works very badly. Caveat Emptor.