Hi - I am resorting to posting this given that McAfee seem unable to resolve this issue. I have been unable to install my licensed product since December 2014 and this still persists despite all attempts to resolve (4 phone calls, 4 hours, lots of frustration). I am told that the problem is a McAfee server issue. I have ended up using a trial version with another e-mail! I have tried the documented work-around (which the McAfee Tech Mac Staff seem completely unaware of) without success. Any suggestions other than use a different product from another company?
Moved to MAC Products for faster assistance.
Other threads here suggest disabling Time Machine to enable installation.
However I am not an expert and will leave that to other here.
Please let know if you purchased McAfee directly from Website or as part of Service Provider (TV/Internet/Mobile Network). From your Email address i was able to pull up a Trial Subscription as you mentioned.