Yahoo and their mail filters..

Jeff Shultz jeffshultz at
Wed Feb 25 17:58:20 UTC 2009

Micheal Patterson wrote:
> This may be old news, but I've not been in the list for quite some time. 
> At any rate, is anyone else having issues with Yahoo blocking / 
> deferring legitimate emails?
> My situation is that I host our corporate mx'ers on my network, one of 
> the companies that we recently purchased has Yahoo hosting their domains 
> mail. Mail traffic to them is getting temporarily deferred with the "421 
> 4.7.0 [TS01] Messages from temporarily deferred due to 
> user complaints -;
> see"
> The admin of the facility has contacted Yahoo about this but their 
> response was for "more information" when they were told that traffic 
> from my mx to their domain was to being deferred.  I may end up just 
> having them migrate to my systems just to maintain company 
> communications if we can't clear this up in a timely manner.
> -- 
> Micheal Patterson

Yep, it's been happening to us - various explanations - and I've got at 
least one annoyed customer because of it.

Jeff Shultz

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