Only seen this 1 time the suggestion was to follow this
It's probablty already activated but it could also be corrupted.
Uninstall McAfee via Control Panel > Programs
Run the MCPR cleanup tool listed under "Useful Links" at the top of this page
Reinstall your software from your online account.
If that doesn't help, then contact Technical Support via the link under Useful Links.
its working propertly. thanks