Why not uninstall it and get a new one. Even if it's one of the free ones noted in the discussion at http://forums.cnet.com/5208-6132_102-0.html?forumID=32&threadID=238606&messageID=2432058
Bob
I have a Dell Dimension desktop (approx. 4 years old) and I
cannot open my McAfee anti-virus software nor can I run a
virus scan. When I power on my computer it looks like McAfee
is opening up and I see the "M" in the system tray, but
when I double click or even right click to open it, nothing
happens. Also, I am no longer receiving live updates. I am
running Windows XP SP2. If anyone can help me out, I'd much
appreciate it.

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