mchain
27
All work suggested so far is to avoid the use of a factory restore. Unfortunately, that may be the final outcome after all this is done.
Suggest using Revo Uninstaller to get rid of System Mechanic and any remaining folders. Not surprised that it does not seem to have an uninstaller or a link to it. Always a symptom of poorly engineered software; this omission is sometimes done on purpose. Revo has a Hunter function that will allow you to directly remove it, plus there is a free version and a trial, more advanced version good for a 30 day full-use license.
You can get it here: http://www.revouninstaller.com/start_freeware_download.html
Suggest running around this site to learn as much as you can about this program before you use it.
As always, create a System Restore point just before you begin.
Addendum: Be sure to back up all personal files first if you choose to do a factory restore, as all personal files will be irretrievably lost when this is done. This is why a registry cleaner of any sort is not recommended as it can damage Windows operation and functionality. Plus, troubleshooting can be very arduous and time-consuming vs. doing a factory restore.
Offer to call someone such as essexboy still stands. He may know of a registry fix or two that may get you on your way.