Outlook continually propting for autodiscover password, need to re

Outlook 2010 is continually popping up a credentials box that's asking me
over and over to enter a password for an autodiscovery process, but the
server (autodiscover.ihostexchange.com) is not the server associated with my
account. How can I modify configuration in order to stop these requests? The
ihostexchange server is related to an old account I had at another provider
in the past. Note that Outlook picked up on that fact after a fresh install
of Office, and I had to manually configure for my actual email
account/service after autodiscover failed trying to reach the old service.
So, my email and Exchange services are running just fine, but for some reason
the autodiscover information for the old machine is still in there. I
searched the registry for the server address but found nothing.

Ideas?

Thanks.

greg