Mail delivery to anything xxxxx.xion.oxcs.net

Jun 2, 2024
15
1
3
Since switching to use PMG as my preferred inbound/outbound mail relay I've noticed an issue. Any client email being delivered to any of the servers that are hosted by oxcs.net are being bounced back saying "lost connection with mx001.webcom.xion.oxcs.net[135.148.130.75] while performing the HELO handshake"

Server hostnames in logs are like this...

mx###.webcom.xion.oxcs.net
or
mx###.netsol.xion.oxcs.net
... etc. The start is often mx001, mx002 or mx003 etc. Not sure what the webcom or netsol stands for but the oxcs.net is "Open-Xchange.com".

Anyone else come across and issue sending email to those servers? I've used telnet on port 25 manually and connected to the server and manually type the HELO, rcpt to, mail from, etc commands it accepts the email and it sends so its not an IP blocking issue or anything like that as the manually email sent via telnet commands works.

Any advice appreciated.

Thanks, Paul.
 

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