Technology & MSG

1&1 Refuses To Accept Mail From Me

Jun 15th, 2007 by Alex

In the past two weeks 1&1 Internet has stopped accepting mail from my mailserver. I get the following error whenever I send an email to them or one of their customers: “421 mails from 71.127.149.126 refused: local dynamic IP address 71.127.149.126″

Now I utilize greylisting so I’m familiar with sending the user a 450; essentially saying “something is wrong and I can’t talk to you now, but do try again later.” If they try again after a set amount of time I process the sender’s mail. But the 421 from 1&1 is different in that they never accept the mail. Instead it builds up in my queue for a few days until Postfix considers it undeliverable and deletes it.

A quick Googling indicates that this is likely a blacklist of some sort that contains what is believed to be dynamic IP ranges, but not an RBL. More likely an internal list, specific to 1&1 (and hence the “local” portion). The problem is that I’m not on a dynamic IP, so I sent off an email to their postmaster.

3D2AD41FF      1012 Fri Jun 15 07:31:18  contact@moundalexis.com
   (connect to mxi00.1und1.com[212.227.15.134]: server refused to talk to me: 421
   mails from 71.127.149.126 refused: local dynamic IP address 71.127.149.126)
                                         postmaster@1and1.com

Crap. You’d think they would accept anyone’s email to postmaster or abuse… but they don’t, and my only way to contact 1&1 without being a customer gets shoved into the black hole. That’s got to be a violation or something, even if only one of best practice and good form.

1&1 is host to many people’s web sites and email. When they were starting they were offering absurdly cheap hosting packages that a lot of people took advantage of for placeholder sites. So it isn’t suprising that I have a few mailing lists with 1&1 subscribers. I currently have two of them submitting support tickets to find out why they aren’t receiving mail from my system.

Another thing to note. I’m not sending spam. This is all legit mailing lists to which 1&1 customers have subscribed of their own free will. Even so, I double checked a bunch of things regarding the mail server.

71.127.149.126 is a static IP on business-class service
Neither the IP or hostname is on any public blacklist
The sending domain has proper forward and reverse DNS entries
I publish up to date SPF records, since some providers (Verizon) look at them
I send RFC-compliant emails

What more is there for me to do? Hell, I got through AOL’s application process to send bulk mail to their members. That’s no easy feat, and I don’t send nearly as much email to 1&1 as I do AOL.

From my mail log, you can see that it isn’t just one of their mail exchangers, but all of them.

Jun 15 07:31:18 vision postfix/smtp[65362]: connect to mxi00.1und1.com[212.227.15.169]:
   server refused to talk to me: 421 mails from 71.127.149.126 refused: local dynamic
   IP address 71.127.149.126   (port 25)
Jun 15 07:31:19 vision postfix/smtp[65362]: connect to mxi01.1und1.com[212.227.15.150]:
   server refused to talk to me: 421 mails from 71.127.149.126 refused: local dynamic
   IP address 71.127.149.126   (port 25)
Jun 15 07:31:19 vision postfix/smtp[65362]: connect to mxi01.1und1.com[212.227.15.186]:
   server refused to talk to me: 421 mails from 71.127.149.126 refused: local dynamic
   IP address 71.127.149.126   (port 25)
Jun 15 07:31:19 vision postfix/smtp[65362]: connect to mxi00.1und1.com[212.227.15.134]:
   server refused to talk to me: 421 mails from 71.127.149.126 refused: local dynamic
   IP address 71.127.149.126   (port 25)
Jun 15 07:31:19 vision postfix/smtp[65362]: 3D2AD41FF: to=, relay=none, delay=1,
   status=deferred (connect to mxi00.1und1.com[212.227.15.134]: server refused to
   talk to me: 421 mails from 71.127.149.126 refused: local dynamic IP address
   71.127.149.126)

I want this to be fixed. My only recourse at the moment is to remove the 1&1 subscribers from my mailing lists or somehow contact them to change to another provider (at least for my lists).

Update: This was fixed by an ESOL tech after a customer opened a case with 1&1 customer support.