Scenario:
Client contacted me to implement Exchange 2013 in their existing organisation.
Old server is Exchange 2007 installed on a Windows 2003 x64 server
The old server is also a Domain Controller (the only DC)
A UC certificate has been purchased & installed on the new server.
All clients are running Outlook 2010
Problem:
The problem is that after moving mailboxes - the outlook client still attempts to connect to the Old server.
A new user with a new mailbox created on the New Exchange 2013 has the same issue, autodiscover resolves OK, but the SSL error that is presented shows the self-signed cert on the old server.
Accessing the mailbox via OWA is OK indicating that the mailbox is working & mail flow is OK (all mail is routed via the Exchange 2013)
Running "Get-ClientAccessServer |fl identity,autodiscoverserviceinternaluri" on the Exchange 2013 gives the correcthttps://autodiscover.domain.com.au/Autodiscover/Autodiscover.xml for the Exchange server and reports https://oldserver.domain.local/Autodiscover/Autodiscover.xmlfor the old server.
There is a DNS zone to the domain.com.au on the internal DNS server and there is an entry for autodiscover that resolves to the Exchange 2013 server.