When a sunbirdinc.com account sends an email to an earthlink.net address, the following message bounces back:
ToSomeone@earthlink.net
host mx1.earthlink.net [209.86.93.226]
SMTP error from remote mail server after MAIL FROM: <FromSomeone@sunbirdinc.com>:
550 IP 199.79.63.190 is blocked by EarthLink. Go to earthlink.net/block for details.
Why/how would this 199 IP be delivering the message to earthlink? The sunbirdinc.com mail server is different. The only association I can find is webhostbox.net.
DNS info:
MX: sunbirdinc.com --> sunbirdinc.com
A: sunbirdinc.com --> 208.91.199.49
PTR: 208.91.199.49 --> bh-26.webhostbox.netPTR: 199.79.63.190 --> 199.79.63-190.confluence-networks.com
A: confluence-networks.com --> 208.91.198.88
PTR: 208.91.198.88 --> md-75.webhostbox.net
Side note:
Earthlink doesn't like the 199 IP because it's flagged by Cloudmark.
Cloudmark doesn't like it (at least partly) because the PTR domain is generic.