Seems pretty clear, you should avoid system mechanic in the future. Avoid all such programs in the future. When they aren't outright lying in their advertisements, they're usually doing things that are more likely to cause problems than resolve them. Be particularly wary of registry programs. Those more than anything have been the source of much woe to people.
At this point you may be left with few options besides formatting. Shouldn't be any activation worries so long as it's on the same system, just the hassle of reinstalling and configuring everything.
I have had more disastrous troubles with Sys MEchanic than any piece of software except perhaps windows itself. SysMech 9.5 did an auto update and instead of updating, it did a complete reinstall. When the computer restarted I totally lost my XP Pro system and it would not repair nor would the last known good system run. I had to do a complete repair/reinstall of Windows and I have my computer back, removed SysM, and installed bitdefender.
HOWEVER, I am getting these constant Microsoft Synchronization Feeds Send dialog boxes every 2 minutes. And it is driving me nuts. I have to manually delete these or cancel out constantly.
What the heck is that and how do I disable the thing??
I suppose MS is going to tell me I have to get a new authorization code just for repairing my XP Pro...
My Mac runs Win 7 just fine thank you very much. I'd like to use my XP laptop as a frisbee for all the trouble it has caused...