Well, I whould try system restore.If that doesn't work I whould have completly cleaned the hard drive and then reinstal everything starting with the OS your using, I'm going to guess your runing either XP or Windows 7.
I know with some software you might have to do that for the licensing and to make sure everything is completly remove including features you might not relize is there.
Both are life and death solutions thought and assuming you have the dvd for all your applications you use to reinstall everything.
My guess is that when you deleted Solar Fire, it wasn't completly removed and the Atlas still thinks its there when you tried to reinstal it.
Try uninstalling everything from the top down and making sure everything is removed including some features. Then try reinstaling.
If all else fails "Nuke" the hard drive and reinstal everything from the OS.
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