Mail Delivery Failed

[adpint]

ff 3.0.15
am receiving mail but select sends are failing.


User-Agent: RoundCube Webmail/0.3-stable
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset=UTF-8

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

  xxx@xx.xx.com
    SMTP error from remote mail server after initial connection:
    host cdptpa-smtpin01.mail.rr.com [75.180.132.243]:
    554 5.7.1 - Connection refused. IP name lookup failed for 67.43.61.4

[JohnDoh]

I think this is a problem with your SMTP server setup, not RC. Check that you have correct reverse DNS setup for 67.43.61.4, lots of mail servers check from matching reverse DNS before they will accept a connection from another server to deliver mail.