I am able to shut down all McAfee services except Real-Time Scanner using either Computer Management-Services or msconfig. When I try to shut down RTS, I get an error message telling me that I need to log on as an administrator.
I am logged as the administrator. It is the ONLY account I have. I am running XP-MCE.
Select the option "at computer restart" while turning off virus scanner, so when you restart your computer next time, McAfee will start it's mcshield service...so you can have your work done till then.
I shut down everything including spyware and system guard. You say it cannot come back on on its own, but it does. I used Task Manager to shut it down after Security Center would not shut it down and less than a minute later it started back up again.