McAfee/AOL & Norton

Worked on a friends machine that had Norton installed. Ran the
uninstall, the file remover from Symantec, and cleaned everything I
could find from the registry. The AOL Virus Scan (McAfee) won't run
because it thinks that Norton is still installed. Does anyone know what
registry key or file McAfee is seeing that tells it that Norton is
still installed?
I finally gave up and installed Avast to give him virus protection, but
he would still like to use his AOL package.
Any Clues?

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