Problems sending mail to yahoo?

Edward B. DREGER eddy+public+spam at
Thu Apr 10 18:41:36 UTC 2008


I've been tempted to implement sort of a "reverse blacklisting".  If an
(MX|provider) trips a 4xx threshold, have the local MTA s/4/5/ on emails
to the problem (MX|domain).  If it trips a 5xx threshold, including
"upgraded" 4xx responses, simply refuse delivery altogether at the local

"You don't like our email?  Fine.  You won't see it."

We've observed good success convincing people to switch away from
overly-draconian email providers... so a "reverse blacklist" might not
be as _Wolkenkuckucksheim_ as it seems.  Or, then again, it might. ;-)

Everquick Internet -
A division of Brotsman & Dreger, Inc. -
Bandwidth, consulting, e-commerce, hosting, and network building
Phone: +1 785 865 5885 Lawrence and [inter]national
Phone: +1 316 794 8922 Wichita
DO NOT send mail to the following addresses:
davidc at -*- jfconmaapaq at -*- sam at
Sending mail to spambait addresses is a great way to get blocked.
Ditto for broken OOO autoresponders and foolish AV software backscatter.

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