Emails from one server are not arriving into a users mailbox. We are running SBS 2011 with Exchange 2013 obviously. Firewall is passing on the email to the Exchange server. According to the ProtocolLogs for Exchange the connection with
the remote server stops after "uploading certificate". No error message is received. Log is as follows:
2020-09-21T08:35:22.176Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,0,192.168.102.10:25,139.138.31.225:19818,+,,
2020-09-21T08:35:22.181Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,1,192.168.102.10:25,139.138.31.225:19818,*,SMTPSubmit SMTPAcceptAnySender SMTPAcceptAuthoritativeDomainSender AcceptRoutingHeaders,Set Session Permissions
2020-09-21T08:35:22.181Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,2,192.168.102.10:25,139.138.31.225:19818,>,"220 remote.XXX.com.au Microsoft ESMTP MAIL Service ready at Mon, 21 Sep 2020 18:35:21 +1000",
2020-09-21T08:35:22.191Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,3,192.168.102.10:25,139.138.31.225:19818,<,EHLO esa2.hc241-12.ap.iphmx.com,
2020-09-21T08:35:22.195Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,4,192.168.102.10:25,139.138.31.225:19818,>,250-remote.XXX.com.au Hello [139.138.31.225],
2020-09-21T08:35:22.195Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,5,192.168.102.10:25,139.138.31.225:19818,>,250-SIZE 51445760,
2020-09-21T08:35:22.195Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,6,192.168.102.10:25,139.138.31.225:19818,>,250-PIPELINING,
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,7,192.168.102.10:25,139.138.31.225:19818,>,250-DSN,
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,8,192.168.102.10:25,139.138.31.225:19818,>,250-ENHANCEDSTATUSCODES,
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,9,192.168.102.10:25,139.138.31.225:19818,>,250-STARTTLS,
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,10,192.168.102.10:25,139.138.31.225:19818,>,250-AUTH,
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,11,192.168.102.10:25,139.138.31.225:19818,>,250-8BITMIME,
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,12,192.168.102.10:25,139.138.31.225:19818,>,250-BINARYMIME,
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,13,192.168.102.10:25,139.138.31.225:19818,>,250 CHUNKING,
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,14,192.168.102.10:25,139.138.31.225:19818,<,STARTTLS,
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,15,192.168.102.10:25,139.138.31.225:19818,>,220 2.0.0 SMTP server ready,
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,16,192.168.102.10:25,139.138.31.225:19818,*,,Sending certificate
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,17,192.168.102.10:25,139.138.31.225:19818,*,CN=remote.XXX.com.au,Certificate subject
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,18,192.168.102.10:25,139.138.31.225:19818,*,CN=RRM-SERVER-CA,Certificate issuer name
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,19,192.168.102.10:25,139.138.31.225:19818,*,2A1C3EC200010000000E,Certificate serial number
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,20,192.168.102.10:25,139.138.31.225:19818,*,F64DC4E04BF276A2F00F9382BE444C70BCEAE823,Certificate thumbprint
2020-09-21T08:35:22.227Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,21,192.168.102.10:25,139.138.31.225:19818,*,remote.XXX.com.au;XXX.com.au;SERVER.RRM.local,Certificate alternate names
2020-09-21T08:35:22.257Z,SERVER\Windows SBS Internet Receive AUBEND-DC1,08D85A7B5EC67081,22,192.168.102.10:25,139.138.31.225:19818,-,,Local
Does anyone know why this abruptly ends without giving an actual error?