I'm not sure how one knows what version of Window is installed. Mine says 'Microsoft Windows XP, Home Edition, version 2002, service pack 3' I don't actually see anything that says Version 7.
I'm more than a little concerned that Piriform offers a download that damages an operating system as commonplace as Windows 7, if that's what I have. There is also, as far as I can see, no way to contact the company directly for a fix. Just chatting with other users for their opinions is something, and I appreciate all your help, but at the end of the day, Piriform should have some resolution to simply re-installing what its product has removed.