Is this a current version of McAfee software 'requiring' Flash Player 13? If so, I'd be very suspicious as Flash Player 13 is 5 years old and there's a host of security issues fixed since then. Refer to -player.html for a list of security updates released since Flash Player 13. We strongly recommend against installing any older version of Flash Player, especially something that is as old as Flash Player 13. Furthermore, all browsers block old versions of Flash Player. Even if it were installed, you'd be prompted to immediately update upon attempting to use it.