Every time I dl AA, I seem to get a virus with it. I've uninstalled, quarantined the virus, and re-dl'ed from a different server and I get the same thing. The damn virus restarts my comp at random times.
It's not AA, unless the site you are DLing from is shooting something to you. Try another site.
Also, if it's not cleaning, it might be a form of a boot virus. Shutdown and unplug the power cable for 10sec or so. Plug it back in and try it again. I had a boot virus for a while that would give me funny crap - I did the unplug and everything went back to normal.
If you can't get anything to work, head to www.16aa.com and post up your problem in our general forums. Tell em Hollow sent you and you should be able to pick our resident geek's collective minds on the problem.