Gees that message is really old have not seen that in ages. What version of Mcafee are you running. I would dare to ask are you running a registry cleaner and or say Glary utilities etc? It has been reported some cleaners delete required Mcafee registry keys.
The support doc on this issue is here
Finally as a last resort uninstall McAfee via Control Panel, then run the MCPR removal tool listed under Useful Links at the top of this page, reboot and reinstall from your online account.