We have 4 mail servers (mail1.contoso.com, mail2.contoso.com, mail3.contoso.com, mail4.contoso.com).
Mail1 & Mail2 are Exchange 2007 and Mail3 and Mail4 are Exchange 2010.
We recently had to remove Mail3 from the organization but Outlook users are still trying to authenticate with that server.
Weird thing is Mail3 and Mail4 have absolutely no mailbox accounts! They were built for a migration that never happened.
Question: How do you remove mail3 and mail4 from handling Outlook authentication requests? OR How do you specify which exchange servers to authenticate Outlook users?