e-message.retn.net has no MX records.
Question and response
Question
dig e-message.retn.net. MX
Answer
The response has no answer records.
Authority
retn.net. 86400 SOA nsa.retn.net. noc.retn.net. 2026020400 7200 3600 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0