26 Mar
2014
26 Mar
'14
10:39 p.m.
Jan Henkins said:
Hmm, that sounds like standard greylisting to me. I do
it myself on my
server, cuts out at least 60% of the spam I get.
I greylist too (see past posts here) and I find it to be more
effective than that.
But this is Yahoo using a 421 error to refuse to accept mail
permanently - see the error message they actually send:
"421 4.7.1 [TS03] All messages from x.x.x.x permanently deferred.
Retrying will NOT succeed. See
http://postmaster.yahoo.com/421-ts03.html"
.. and they mean it. (Even if they get the URL wrong.) No matter how
many times it is resent, or how long is between resends, it is not
accepted every time. This isn't greylisting, this is blocking replies
to their own users' emails. I can't even reply to emails I send from
my own Yahoo account.
Oh, if I try sending an email to mail-tester.com, I get a 9.8/10 score
- the 0.2 deduction being because the text of the email ('test')
doesn't look like a normal email. SPF pass, DKIM pass, reverse IP
lookup pass etc.
Ian