Not sure but Microsoft withdrew some recent updates for Win 7 and 8 due to strange problems like this. Can you boot into Safe Mode and start System Restore to an earlier date?
I can't get to safe mode.
I don't think this has anything to do with your McAfee software but of course one never knows. Short of asking Technical Support for help (free by phone or online chat - see link below) all I can suggest is try either of the following:
http://www.eightforums.com/tutorials/26095-repair-install-windows-8-a.html - you wont lose any data
http://www.eightforums.com/tutorials/2302-reset-windows-8-a.html - you will lose all your data.
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Please check if you are able to open Task Manager by pressing CTRL+ALT+DEL when you see the black screen. Once task manager is open Click on File > New task > explorer.exe > OK.
Post back once you are able to recover Windows explorer and for further instructions..!