We migrated to Exchange 2016 this past weekend. Updated the DVR to point to the new server but alerts are not coming through. I tried using Get-MessageTrackingLog to see whats happening but I don't see the messages coming in to the server from the DVR. i imagine there is some issue and the server is rejecting the connection from the DVR but I am not sure how to troubleshoot to see why it is not allowing the connection. The DVR has a setting for outgoing auth and which port to use. I can send email from outlook using the same settings and it works. Any ideas ?