If McAfee is involved at all, then usually simply running the McAfee MCPR tool will clear the problem completely.
Download the McAfee removal tool from:
http://download.mcafee.com/products/licensed/cust\_support\_patches/MCPR.exe
Click Save, and save the file to a folder on your computer.
Navigate to the folder where you saved the file.
right-click on MCPR.exe and select 'Run as Administrator' to run the removal tool.
when complete, reboot.
A lot simpler and less dangerous than messing in the registry! ;)