Problems sending mail to yahoo?

Thu Apr 10 19:43:15 UTC 2008

Frank Bulk wrote:
> Q> Does Yahoo! use "greylisting" to reject messages?
> 
> A> No.
>    The most commonly understood form of "greylisting" is where an 
>    SMTP server will reject every message the first time it is 
>    attempted, and then accept it if the sending server retries 
>    later. The theory is that spammers won't retry messages, while 
>    legitimate senders will.
> 
>    Yahoo! does not utilize this method.
> 
> http://help.yahoo.com/l/us/yahoo/mail/postmaster/postmaster-05.html

Whatever they call it is immaterial. The end result to our system is 
indistinguishable from real greylisting. Perhaps there's a tiny fraction 
that aren't ever deferred, but in general I find the majority of our 
queue is destined to @yahoo.com addresses.

I think I'll followup on the other posters ideas of:

1) Implementing a separate outbound gateway just for yahoo.com
2) Advising users to switch to gmail.