Yahoo and their mail filters..

Wed Feb 25 14:36:12 UTC 2009

On hotmail's defense at least their support contacts will respond to your emails. It may take a few rounds of proving that they are 'blackholing' your email and them saying 'no were not'..but after a few times of that you know exactly what to say when submitting a ticket to them (ie I sent this email to your testing account at xx:xx pm, I cc'ed my address xxx at hotmail.com and it wasn't received and here are the logs showing your servers accepted the email.). 

-r

-----Original Message-----
From: Erik (Caneris) [mailto:erik_list at caneris.com] 
Sent: Tuesday, February 24, 2009 10:11 PM
To: Joe Abley; Micheal Patterson
Cc: nanog at nanog.org
Subject: RE: Yahoo and their mail filters..

Ditto. They appear to use some strange form of greylisting combined with blocking. What seems to help is SPF and PTRs that match the EHLO your MTAs will send. We didn't implement Domain Keys / DKIM. 

On a related note, don't get me started on Hotmail. They used to (still do?) silently swallow mail into a black hole after accepting it. No NDR, no spam folder, just good ol' mail shredding without anyone knowing. Again, SPF and PTRs seem to help. 

Oh yeah, make sure you're not sending spam to them. That might help too. ;)

Erik
________________________________________
From: Joe Abley [jabley at hopcount.ca]
Sent: Tuesday, February 24, 2009 9:41 PM
To: Micheal Patterson
Cc: nanog at nanog.org
Subject: Re: Yahoo and their mail filters..

On 24 Feb 2009, at 21:27, 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?

Yes. Everybody else.

Joe