I hope this is the right forum. I have a problem with emails from a potential customer who is using mxlogic for their email service. Obviously I'd like to stay in contact with them via email, but we are running into problems.
My setup: I am running my own email server for my company's domain beckmann-consult.com (and a few other domains owned by my company). Email server is not and never has been listed on any spam / blacklist, and is not used for anything remotely like sending spam. With the exception of a few 554 false positives over the last 10 years, I have never had any problems sending or receiving emails either.
My problem: I can send emails to the potential customer, but when they send a reply, nothing is received. I have looked at my email server logs, and the only clue I can find is this excerpt:
2016-04-18T19:08:15.390313+02:00 <server name withheld> postfix/smtpd: connect from unknown[126.96.36.199]
2016-04-18T19:08:16.074276+02:00 <server name withheld> postfix/smtpd: Anonymous TLS connection established from unknown[188.8.131.52]: TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)
2016-04-18T19:08:16.784360+02:00 <server name withheld> postfix/smtpd: BF6601F5045: client=unknown[184.108.40.206]
2016-04-18T19:08:20.617130+02:00 <server name withheld> postfix/smtpd: disconnect from unknown[220.127.116.11] ehlo=2 starttls=1 mail=1 rcpt=1 quit=1 commands=6
18.104.22.168 is the IP address of a mxlogic outbound server, as far as I can tell (whois lookup). Obviously, the mxlogic server is trying to set up an encrypted SMTP connection with my server, but for some strange reason, that connection is broken before the message itself is sent (no mention of if in the logs). I can't figure out from my end what is going on here. How do I get somebody at mxlogic / Intel to look at this?
Hi there mbeckma2000,
The sender of the emails (SaaS customer) will need to contact their support representative to request assistance with this issue. We will likely need to look at logging details on our side but will need to have a request opened by our customer.
Intel Security Technical Support