So i see this:
2018-11-02 10:49:27 1gIbsF-0000TW-1C H=mail.domain.com [IP Blanked for security] TLS error on connection (send): The specified session has been invalidated for some reason.
2018-11-02 10:49:27 1gIbsF-0000TW-1C == ebmnc@zteknology.com R=smarthost T=remote_smtp_smarthost defer (-45) H=mail.domain.com [IP Blanked for security]: SMTP error from remote mail server after pipelined MAIL FROM:<untangle@domain.com> SIZE=2090: 421 4.4.2 Message submission rate for this client has exceeded the configured limit
2018-11-02 10:49:27 1gIbsF-0000TW-1C H=mail.domain.com [IP Blanked for security] TLS error on connection (recv): The TLS connection was non-properly terminated.
Couple things re: this log. The ebmnc@zteknology.com doesn't exist. Is there a way to figure out where that connection is coming from so I can block it. It also looks like it's a TLS issue on my Exchange box?