Hello!
I have some strange troubles with my Ex2013 servers. There are 3 exchange 2013 servers in organization, 2 of them are included in send connector to smart host. 3rd is not. Today in queues on 3rd server I see queue to smart host, that is always in retry state. If I include this server in send connector messages are sending normally. And now I don't understand why messages sent outside organization are coming to server not included in send connector. Configuration: Windows Server 2012 R2, Exchange server 2013 CU5.