Outlook 2013 connecting to an Exchange 2016 server and getting a certificate error. The hostname it has an issue with is the internal name of the server 'mail01.domain.local' We have a legit cert for mail.domain.com and it is the only certificate in Exchange. All the URLs in Exchange are pointed to mail.domain.com. Been through all the vdirs in ECP multiple times. I don't see mail01.domain.local in there anywhere.
Where is it picking up mail01.domain.local from in Outlook?
One thing I noticed when looking at the settings on the client is that is does not appear to be using Outlook Anywhere to connect. I don't see the option to connect via RPC over HTTP. If I try and manually set up Outlook Anywhere/RPC over HTTP, it works....but seems to drop the RPC over HTTP after a subsequent close/open of Outlook. There is still an Exchange 2010 server in the environment, but should be going away next weekend. I'm hoping there is not total fallout on the clients when the old Exchange server is decommissioned.
Funny thing is the Microsoft Remote Connectivity Analyzer says Outlook Anywhere is good.