I have recently experienced Firewall, real time scanning and virus protection off. All the forums I looked at say uninstall then reinstall, that did not work for me, however when I browsed ' MY ACCOUNT ' with Mcafee I discovered that my credit card details were incorrect. When corrected an instant fix ensued.
Hope that works for you,
So it says enable in the firewall settings ie it is disabled and you can enable it? Ie eb and email protection /firewall turn on.
If it disables immediately you may have a virus some turn off Mcafee components
But first set firewall to defaults restart Pc.
If no go run Mcafee virtual technician from the tech support site and see if it sees anything
Run in order
stinger this and getsup do not auto update so need redownloading to get latest versions
Malwarebytes from here...
If still an issue call Technical support from the link further up.