Prodigy.net Reverse DNS Lookup is Broken
Every day one or two (usually important!) emails sent to me are bounced by a prodigy.net server claiming the sending server fails reverse DNS lookup. Investigations show the servers all have valid MX and PTR records. In fact, if the same message is resent through the same server it is accepted and delivered to me.
This is the relevant portion of a bounce back message:
host al-ip4-mx-vip1.prodigy.net[126.96.36.199] said: 550 5.7.1 Connections not
accepted from servers without a valid sender domain.alph755 Fix reverse DNS
for 188.8.131.52 (in reply to MAIL FROM command)
This is the relevant header from a message that was accepted, probably because it hit a different system in prodigy.net. Note the (same) IP address of the server and the correct rDNS hostname:
Received: from mx04.nic.name (mx04.nic.name [184.108.40.206]) by alph754.prodigy.net (Inbound 8.15.2/8.15.2) with ESMTPS id 069FRYZN098085 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL) for <[email scrubbed]>
Please forward to the DNS network team. Do not send me to abuse_rbl. This is not a blocked address or blacklist issue.
Network Solutions has a page online documenting a similar problem from 2018. It took them a week to find the correct person in AT&T and get the situation corrected. I'm hoping to resolve it in less time.