Posted in the wrong area so have moved provisionally to Consumer > Mobile. You don't indicate which product you are using so am guessing.
Try the FAQ: The device is locked and you forgot your Mobile Security or WaveSecure six-digit PIN if that is no help there is a link to free phone or online chat support at the top right of that page or in my signature below.
Toronto ▪ Canada
Volunteer Moderator - Consumer Products
I CAN'T HELP PRIVATELY - PLEASE POST IN THE FORUMS
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Can you help by telling us what McAfee product you think is responsible for this, and what version you are using? Can you post a screenshot of the problem?