AOL 421 errors

Jim Popovitch jimpop at
Wed May 3 21:14:00 UTC 2006

Matthew Black wrote:
> We've noticed a surge in 421 e-mail errors from AOL.
> Message soft bounced for '', '4.3.2 - Not accepting messages 
> at this time ('421', [': (DYN:T1) 
> AVAILABLE']) []'
> It seems as though they've tightened down their policies.
> We're pretty good at preventing spam with our IronPort
> anti-spam gateways and internal policies.
> We've also subscribed to their FBL notification service.
> I'm surprised at the types of messages AOL customers consider
> as spam. Anything and everything: university admission acceptance
> notices; instructor class assignments; photos from friends; etc.


I've been dealing with this too for 6 days now (2 of them while away on 
vacation).   AOL Postmasters, while very friendly and nice, have 
provided me more "answers" than one could fit in a magic 8-ball.  We've 
got 334 list members who are barely 
receiving email that they want to receive.  We run Q&A lists for 2 
non-profits, one technical, the other cancer related.  Users post 
questions, experienced users provide answers.  Nothing more.

I've have had FBLs setup and been on AOL's whitelist for 2+ years now, 
and I am about at my wits end with dealing with them.  It is no wonder 
that their user base is shrinking, and it is sad that they treat their 
own customers with such broadly applied brushes.  Sure there are spam 
problems, but to block requested email from reaching interested users 
(some of them being AOL employees themselves) is just plain wrong.

I will say this, numerous AOL postmasters have told me that they have 
issues with their FBL system (I've got 2 open tickets on that alone).  I 
have also been told that our email should not be being blocked/delayed, 
and I have open tickets on that too.  But that in no way explains to me 
why the have happily accepted an average of 162332 emails each month 
from us for the past 3+ years and that now they don't want it.  :-)

It is worth pointing out that Yahoo!, Cox, GMail, HotMail/MSN,, 
Earthlink, Verizon, and SBC Global happily receive almost similar 
amounts of email from us without the need for whitelists, FBLs, etc. 
What is funny is that the domains have SPF records which AOL likes, but 
they don't yet have DomainKeys which Yahoo! likes.  AOL could learn a 
*lot* from their competition when it comes to handling email.

-Jim P.

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