I have been getting alerts that my computer is not protected .It shows that the real time scanning is shut off. I turn it back on and it is ok . When I return to the computer there is the alert again sometimes hours pass sometimes only a few minutes for it to revert to being turned off
Maybe that will help. Alternatively did you ever have another AV installed? If so you need to run its removal tool as bits of it may still be installed.
Real Time scanning depends on various factors, I would recommend you to follow Peacekeeper Post first and if the issue still persist. You may have to run stringer tool.
Kindly go through how do you use Stinger? Using the below link:
Also, you can download & run the McAfee Stinger Scan using the following link: