[Mailman-Users] Sending domain does not exist but it actually does?

[Mark Sapiro]

On 03/22/2018 07:10 AM, Jayson Smith wrote:
> 
> <<< 550 #5.1.8 Domain of sender address <xxxxxxx-bounces at xxxxxxx.com>
> does not exist
> 554 5.0.0 Service unavailable


I would check the following in DNS

Does xxxxxxx.com have an A record (not a CNAME)?
Does the IP address in that A record have a PTR (rDNS) back to xxxxxxx.com?
If you support IPv6, check the same things for the AAAA record.


-- 
Mark Sapiro <mark at msapiro.net>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan