Peter wrote:
I have a client who complains that one of their own clients cannot send mail
to them. The sender has performed a simple SMTP transmission and receives
the following error:
SMTP Error 4570:
Illegal response to the sender(550):
550 5.7.1 H:MXB<<SMTP client IP>>Connection refused to due abuse
I realize this is a generic MTA question but I figured some may want to
comment since it may be a spam abuse issue. I have gone to dnsstuff.com and
checked the sender IP and all is well.
PM
It sounds like someone has setup a rule at the MTA level to block that
IP or netblock.
If it's a private DNSBL it won't appear in most of your public checks
--
Mr Michele Neylon
Blacknight Solutions
Hosting & Colocation, Brand Protection
http://www.blacknight.ie/
http://blog.blacknight.ie/
Tel. 1850 927 280
Intl. +353 (0) 59 9183072
UK: 0870 163 0607
Fax. +353 (0) 59 9164239
