I had the same problem and solved it like this:
Go to "My Account" and check if your subscription is still active. If not, re-activate it. Check out, then right-click on the McAfee-icon in the lower right corner of your monitor. Choose "Verify subscription" or something like that (I have a Dutch version). This solved the problem on my PC. Hope it works for you too.
Message was edited by: PeterFleming on 9/8/10 4:33:10 PM CDTMessage was edited by: PeterFleming on 9/8/10 4:56:51 PM CDT