We have an Exchange 2010 server configured to send and receive mail on several accepted domains for Outlook Anywhere, with a UCC cert addressing each mail.domain.com and autodiscover.domain.com, mail.otherplace.com etc.

This worked fine until an SSL domain validation cert for one of the additional domains - where the www.otherplace.com is hosted outside our org - expired. Now Exchange users in mail.otherplace.com get an expired cert warning for otherplace.com when connecting to our mail.domain.com portal. They still get mail, but with a repeated popup in Outlook 2007 and 2010.

If I understand it correctly - Outlook autodiscover connects by first polling otherplace.com/autodiscover - which is the outside www server with the expired cert before continuing on to autodiscover.otherplace.com - which is where the MX record points to our in-house Exchange UCC.

I'm trying to find out if we should: 1) turn down all mail functions on the outside webserver 2) delete the expired (useless for an informational site) cert on the outside webserver 3) renew the cert for otherplace.com on the outside webserver - or something completely different? Many thanks in advance for your thoughts.