You should contact Technical Support Chat via the Useful links at the top of this page. They are available 24/7 and can remote connect into your computer provided you give them permission to do so and have many tools at their disposal than we do here on the forum.
When you removed the program did you use the removal tool? The MCPR tool is found in the removal FAQ in the useful links tab at the top of this page.
Before reinstalling run the preinstall tool
Then reinstall then check with chat if still an issue.
Thanks for the suggestions.
I tried the removal tool (it said it was successful) and the preinstall tool but they didn't make any difference.
Just as an aside, the link to the removal tool in Useful Links doesn't work - it comes up "article not found" so I had to search for it elsewhere.
It looks like I'll have to use the online help, but I'm a bit reluctant - I've been a victim of computerised fraud before with my credit card and since I do online banking it makes me wary.
In the meantime, I noticed that when I am in Safe Mode, all the Mcafee stuff seems to work except real time scanning.
I also noticed that I can't start up in Safe Mode With Networking as it hangs like it does when I try to start normally.
Chat safe trust them if no success ask to escalate and a higher tech will come and call you.
I have had them access my PC so you are totally safe with them. Sometimes ansers are a tad canned that is why I suggest escalation if no solution