ErrorFix and RegCure do not actually fix problems...they simply delete registry keys which they think (but do NOT know for sure) are unnecessary. Thus, they could accidentally fix a problem but, far more often, they create problems. Also, McAfee's backup/restore does not include the operating system, just personal files. Thus, you have not actually restored your system yet.

To perform a restore operation, insert the first CD/DVD from your computer manufacturer and reboot your computer, booting to the disc rather than Windows. Follow the instructions to reinstall Windows, which will wipe the entire contents of your hard drive, including personal files. After Windows is reinstalled you can then restore your personal files from backup and start fresh. Afterwards I would advise against using registry cleaners, as they can create the problem you have encountered.


P.S. Before you perform a full restore, you may want to run System File Checker first to see if it can correct the issue.