I've got a customer who uses email addresses that they get along with their Hosting package, they been using the same hosting and emails for at least 5 years. Within the last two weeks they are getting dozens of bounced email's messages that they are sending that are work proposals from recipients with Verizon.Net and Aol.Com email address.

The return message is:

From: Mail Delivery System
Sent: Wednesday, August 30, 2017 9:41 PM
To: Jim@<Customers Domain>.com
Subject: Undelivered Mail Returned to Sender
This is the mail system at host qproxy1.mail.unifiedlayer.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
<<Recipiants Email Address>@aol.com>: delivery temporarily suspended: host
    mailin-01.mx.aol.com[] refused to talk to me: 421 4.7.1 :
    (DYN:T1) https://postmaster.aol.com/error-codes#421dynt1*

or sometimes:

Reporting-MTA: dns; qproxy6.mail.unifiedlayer.com
X-Postfix-Queue-ID: 7BEAA140B7B
X-Postfix-Sender: rfc822; Jim@<Customers Domain>.com
Arrival-Date: Thu, 24 Aug 2017 10:05:30 -0600 (MDT)

Final-Recipient: rfc822; <Recipiants Email>@aol.com
Original-Recipient: rfc822;<Recipiants Email>@aol.com
Action: failed
Status: 5.2.1
Remote-MTA: dns; mailin-03.mx.aol.com
Diagnostic-Code: smtp; 521 5.2.1 :  AOL will not accept delivery of this

or this

Reporting-MTA: dns; qproxy5.mail.unifiedlayer.com
X-Postfix-Queue-ID: 819436B44F
X-Postfix-Sender: rfc822; Jim@<Customers Domain>.com
Arrival-Date: Wed, 23 Aug 2017 10:47:33 +0000 (UTC)

Final-Recipient: rfc822; <Recipiants EMail>@verizon.net
Original-Recipient: rfc822;<Recipiants EMail>@verizon.net
Action: failed
Status: 4.7.1
Diagnostic-Code: X-Postfix; delivery temporarily suspended: host
    mailin-01.mx.aol.com[] refused to talk to me: 421 4.7.1 :
    (DYN:T1) https://postmaster.aol.com/error-codes#421dynt1

I've talked to their hosting provider and they basically said "This is not our problem"; I filled out the Aol whitelist request early last week and nothing has changed as far as I can tell; I emailed postmaster@aol.com and asked why the emails are being bounced and no response after almost a week; I talked to Verizon who gave me an Aol support number and I talked to Aol and they said "You are not our customer, there's nothing we can do to help you". I told my customers that basically the people who have the email addresses that we can't send to are the ones that have to complain that the emails they are being sent are bouncing and those people say "I'm getting email from everyone but you so why should I take my time to call Aol for what seems to be your problem?"

I can't help but wonder if this has something to do with the migration of Verizon.net emails to Aol.Com.

So here's the thing, what can I do that I haven't already done? How can I get this fixed?


So you have been hit by a spam protection mechanism. First you have to find out, wether the email(s) get rejected for good reason. Does your customer send explicitely solicited emails only, or does he - sometimes - send work proposals to people who have not asked for this service? If he does send unsolicited emails, he has to stop that, before the situation can change.

As soon as that's sorted out, you may check the technical situation. The system qproxy1.mail.unifiedlayer.com uses an IP address to send mail to other mail servers. Check, wether this IP is blacklisted somehow by using one of the many RBL checking services you easily find searching for "rbl check". If it is blacklisted, follow the blacklist's instructions to get removed. Each blacklist's policy is different, but basically they all tell you the reason for their blacklisting and require to correct the situation.

If your server is not found on any public blacklist, check at AOL.com for their "IP reputation service": https://postmaster.aol.com/ip-reputation - if you are listed there, follow their instructions, including subscribing to their feedback loop system. Use it! They won't care about your problems unless you have been verified using it.

IF YOU ARE SURE your customer's emails are 100% clean, I mean really 100% of 100% clean, so any spam complaints are 100% nonsense - not a single one is for good reason - THEN YOU MAY CONSIDER routing your customer's mails through anoter mail server, which is not blacklisted, until the blacklisting is removed. This may take some weeks! But if there are reasonable complaints, your other mail server will be lacklisted instantly.

I had such a blacklisting some time ago when I started using a new leased root server for mail services. The IP my hosting provider uses was blacklisted at AOL, because a former client of my provider had been sending spam without my provider knowing it. When this customer left, the IP was reassigned to a new server, but it remained blacklisted at AOL, so it hit me. It took some time (about two weeks), but I got it unlisted.

Spam protection is trickey. Some recipients have asked for being subscribed to a mailing list, but later they decide otherwise. Instead of unsubscribing they mark your mail as spam and get rid of it this way. Then their provider rejects your legitimate mails as spam, and if there is more than one such recipient, they may start blacklisting your mail server. This is a common scenario you have to check for.

There are many other possible reasons for your customer's emails getting rejected, but do these checks first - most probably that's all you need to do.

Good Luck! TomTomTom

  • I'll give it a try but they are an electrical contractor and their emails are 100% legitimate; they get called by the customer and go and look at the requested work (take photos if necessary) and write the estimate and send it to the customers email. There is just no way that anything they send could be considered spam. – NormAtHome Sep 1 '17 at 11:19
  • I've checked and my customers domain is not on any blacklist (I checked using MXToolBox.Com) and MXToolBox also checks mail.unifiedlayer.com and it's not there either. The Aol reputation for my customers hosting providers mail server appears to be "Undisclosed", not sure what that means? – NormAtHome Sep 2 '17 at 2:57
  • Yes, that's it, "undisclosed". That means there is a problem, but they don't publicly tell you what it is. And it means, that you have to engage in that feedback loop process at postmaster.aol.com/fbl-request. But I see, that you are writing about your customer's hosting provider's mail server, so it's not your mail server. That means their mail server is blacklisted at aol, and they have to engage in that fbl-request. If they don't, you customer will have to change email provider. – TomTomTom Sep 2 '17 at 9:45
  • Since we were at our wits end trying to get this resolved, I filed a complaint with the FCC and after a lot of wrangling we finally seem to be in touch with people at Verizon that can resolve this. I've been going back and forth with them for more than a week, today they are saying that they think the problem is that our spf record is not configured properly. I looked and this is what it is "v=spf1 a mx ip4:<Hosts IP Address> a:<the businesses domain name> include:<the hosting companys domain> ?all" does there seem to be something wrong with this? – NormAtHome Sep 22 '17 at 22:07

I've had this exact issue a few years back and use O365 (cloud hosted access through GoDaddy for one domain) and Kerio connect (self hosted at another customers site) and here's how to get more insight. Send an email to a Gmail account and look to see if it shows up with a octagon with an exclamation point inside it (mouse over and click on it for details) and also look at the security details. This should tell you how a receiving provider who has not blocked you is viewing your communications. Since providers are looking to fight spam they scrutinize every configuration you can think of. Your DNS records have issues by not implimenting DMARC, DKIM, and SPF in today's standards of spam protection. If you don't have them you are not compliant by today's standards. Lastly you need to have your ISP configure reverse DNS to your IP addresses for your domain name. This is what caused AOL and Q.com from not getting messages.

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