ATT Blocked Email Notification

I've been attempting to deal with a blocked email issue between us and Prodigy (AT&T specifically).

Blocking Message

-----Original Message-----
From: Mail Delivery System [mailto:MAILER-DAEMON]
Sent: Wednesday, January 11, 2012 7:41 AM
To: <internal recipient>

Subject: Undelivered Mail Returned to Sender

This is the mail system at host securemail.mayohospital.com.

I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can delete your own text from the attached returned message.

                   The mail system  <removed> 

host ff-mx-vip4.prodigy.net[207.115.20.23] said:
    553 5.3.0 flpd124 DNSBL:ATTRBL 521<66.***.**.**>_is_blocked.
__For_information_see_http://att.net/blocks (in reply to MAIL
    FROM command)

Unblock Request

I've visited the designated http://att.net/blocks page a couple of times in the last few months, as did our Network Administrator, to request the unblock. Specifically we used the Tools for non AT&T users whose messages have been blocked link and fill out the form.

Near instantly I received a seemingly automated reply from [email protected] which reads as follows:

Dear Postmaster:

We are writing to let you know that we are blocking messages addressed to one of our customers at the domain prodigy.net by one of your customers at domain mayohospital.com. The stream of messages coming from your system appears to consist mostly of unwanted commercial e-mail (UCE, or "spam"). To protect our system and to ensure that it operates well for all of our customers, we have decided to block all messages originating from your system.

Please consult your logs to see what might be causing this situation and how it can be fixed. Then visit http://rbl.att.net/block_inquiry.html to request a removal of the block. Most requests for removal are honored within two days.

The specific error message received by your customer was:
Diagnostic-Code: smtp; 553 5.3.0 flpd124 DNSBL:ATTRBL 521 < 66.***.**.*** 

Thank you for your assistance in helping our respective customers communicate.

Best regards,

The AT&T Mail Team.

Our Logs

I check our logs and make an interesting discovery, which I outlined below in a reply to [email protected] (can you see the impending train wreck though?):

Good morning,

I have checked our outgoing logs to *@prodigy.net for one calendar year and have confirmed that 142 messages have been attempted.

Of those 142 messages, 4 email users on our domain send email to 4 @prodigy.net users.  One of those recipients is a user on both domains and two of the other @prodigy.net recipients are relatives of him.  The fourth @prodigy user has had 114 conversations over 12 months with one user on our domain.  

The logs do not indicate the issues presented in the reply email below and screenshots can be made available of the logs upon request.

Please remove the block or present substantial proof of the indicated issue.  

Thank you,
Mike

I send this email to the address. See the next section.

You Can't Communicate When You Are Blacklisted

If you're estute, you'll have seen this reply coming:

This is the mail system at host securemail.***.com.

I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to postmaster.

If you do so, please include this problem report. You can delete your own text from the attached returned message.

                   The mail system

<[email protected]>: host scc-mailrelay.att.net[204.127.208.75] said:
    521-66.***.**.** blocked by sbc:blacklist.mailrelay.att.net. 521 DNSRBL:
    Blocked for abuse. See http://att.net/blocks (in reply to MAIL FROM
    command)

What Next

At the moment I would like to get in touch with a human and all present routes seem to fail. I'll reach out on Twitter in a moment and we'll see how that works. I'll update as I go and most likely will point to this page in the reach out.

• 1st Tweet

Reaching out to @ATTBusiness @ATT for help on a email blacklist issue.
Went suggested route with no luck. 
Details here http://rabbibob.com/index.php/ATT_Blocked_Email_Notification

• This looks promising: I've been asked to follow a specific ATT social media team member and DM (done).
• Asked to email details to an ATT email address (noted .com - and the email made it through as autoreply received).
• Spoke to an AT&T rep. Very polite, initially pointed me in the direction of what the error indicates, but through discussion she said that she would reach out to technical to have them contact me. I did not discount that it may be a setting on our side and that I'm looking for that hidden thing that makes AT&T's mail servers not like us so we could work from there. /crosses fingers