I would nearly 100% bet that this is a false positive. Key loggers are a
primary target of any antispyware application, including Microsoft
Antispyware.
However--any indication that such is in place is nothing to fool around
with--if AOL doesn't have acceptable tech support, I'd recommend calling
Microsoft PSS:
1-866-pcsafety (if you are in the U.S. or Canada.)
See what they have to say about this issue--removal of a keylogger isn't
usually a simple matter.
If you are not in the U.S. or Canada, call your local Microsoft subsidiary
or number for paid support, and ask for the free help with virus or security
patch issues.
A key logger in place definitely qualifies for this support, even if it is a
false positive.