I believe that you can download the Mcafee file on their website, provided you have your license key and or mcafee account username and password. The last time I installed, I just logged in, downloaded it, installed, and no key was necessary! I now use NOD32, but I doubt it has changed in the last couple of months...
Good luck
(P.S. Mcafee is a pretty good paid anti-virus, but NOD32 can catch alot more than mcafee, heck if I even TRY to download a virus, NOD32 stops it before it even finishes. That's what I call a good AV, and lightweight too!)