I remember the most frightening McAfee situation I ever had to face. After about 4 months away, I turned the computer on and had 4 months of updates. Then came the Windows updates. It took next to forever to complete all of them.
For the record, I always keep the microwave unplugged when not in use, I can't stand the light from it.
The only thing I learned with McAfee and updates, most can be slowly done while you do other things with the computer and while on-line and when the boxer rebellion pops up to tell you to shut down and restart, it can be ignored, then shut down regular, next time the computer comes on it's taken care (at least I think it is). I don't have a pre-scheduled time for full virus scan as that seemed to hinder doing anything else, I now do that manually once a week. Same holds for other pre-scheduled, they seem to tap into other parts of the system and create headaches.