tedm at ipinc
May 12, 2011, 1:54 AM
Post #22 of 43
On 5/12/2011 12:08 AM, Niamh Holding wrote:
Re: Yahoo sent 5.5x as much spam as any other legit provider in April
[In reply to]
> Hello Ted,
> Thursday, May 12, 2011, 7:36:01 AM, you wrote:
> TM> Your welcome to my exclusion list if you want it, I'm not
> TM> going to post it here but anyone who wants a copy can just ask.
> TM> Do you want a copy?
> Of your exclusion list no, but I am asking you to post the evidence
> backing up your unsubstantiated claim to the list.
Others have reported Yahoo doesn't handle 4xx errors properly,
you apparently missed their posts?
If you are a Yahoo programmer and wish to work with me to
correct your servers then please e-mail me offline from your
actual Yahoo corporate account, provide an office extension
at Yahoo, a phone number, and I will call you to arrange to
setup a test mailserver with greylist-milter and you can
send test messages to it and we can log the results, and
get your problem solved.
But if you are not then all I'm going to say is that anyone
who understands e-mail can do the appropriate whois queries that
will establish what I am in charge of in less than 30 seconds,
and draw their own conclusions. I have had problems with users
not getting e-mail when Yahoo's IP addresses were not excluded
from greylisting, I investigated and did not see retries from
Yahoo's mailservers in the mail log file, I excluded Yahoo's IP ranges
from greylisting, the users reported the problems went away. I have not
had to exclude other mailservers on the Internet for greylisting
for this reason. I HAVE excluded some other services that
use server pools because not excluding them delays mail (as
their pool will try different servers until all servers have
been tried then start over and the transmission succeeds) but
no other services have simply failed to attempt to retry as
Therefore I have had it proved to my satisfaction that Yahoo's
mailservers do not retry when greylisted - which breaks
greylisting. Maybe they retry if the 4xx is issued to them
under other circumstances, but I don't care about that.
Obviously, anyone else running the same greylisting
as I am would have had the same experience as there is no reason
Yahoo would single me out from the thousands of other ISPs out
there that use greylist-milter. So they would have to also
exempt Yahoo from their own greylisting. I'm sure this is a
big factor in their spam source ranking.
Once I learned what I learned I moved on to other things and
I did not save all of the evidence just to be able to trot it out
on mailing lists years in the future.
Perhaps since I had that problem Yahoo has changed. But
I'm not going to risk having user trouble again by removing
them from the exemption list. Fool me once, shame on you,
fool me twice, shame on me.