Yahoo - 421 4.7.1 [TS03] All messages permanently deferred

EQ Admin

EQ Forum Admin
Staff member
I have some fairly strict email policies on our outgoing smtp relays at work yet one of them still managed to land on the following Yahoo blocklist. It's interesting that they are permanently using a temporary error condition. The only logic that I can think of for that is to allow a mail systems admin to check their queues and see what is in there before it bounces back to the original senders. More information from Yahoo follows below.

421 4.7.1 [TS03] All messages from x.x.x.x permanently deferred

This error message indicates we are seeing a high volume of messages from your IP address that is a characteristic of unsolicited, bulk emails. While this is a temporary SMTP error code, we do not recommend attempting to resend your messages until you examine your subscription practices and lists, and implement changes to ensure that your messages are sent only to users who have requested it. Please visit this page to review our best practice recommendations.

If you have deployed significant changes or feel you have received this message in error, you may contact our Postmaster team by filling out this form.
 

jparker

New Email
Did you ever resolve this problem. I am experiencing the exact same one and have filled out every form on Yahoo's site, no luck.
 

EQ Admin

EQ Forum Admin
Staff member
Yes, I was able to resolve the problems for my ISP smtp relay pools.

Use the bulk sender form above if needed.

Depending how busy they get it may take a few days to a week to get a response.

As long as you are generally a legit sender and only need to work through a temporary drop in your IP address reputation Yah0oo should be responsive and helpful.
 

jparker

New Email
I did fill out the bulk form, after asking for more info several times, they gave me the following answer (I am not a bulk sender and have never had any blacklist issues):

Thank you for writing to Yahoo! Mail.

We appreciate your responses to our questionnaire.

However, based on the information you have provided us, we cannot
systematically deliver your email to the Inbox at this time. We suggest that you ask your users to set up a filter in Yahoo! Mail to ensure that they get your email messages in their Inbox. Yahoo! Mail users may find more information regarding filters at this page:

http://help.yahoo.com/help/mail/manage/manage-06.html

If you significantly change your policies, please feel free to contact
us again to submit a questionnaire in 6 months, and we will re-evaluate your answers and mailing practices at that time.

For assistance with delivery issues to Yahoo! Mail, please visit:

http://help.yahoo.com/l/us/yahoo/mail/postmaster/

Your patience during this process is greatly appreciated.
 

EQ Admin

EQ Forum Admin
Staff member
How many mail servers, IP addresses, and what kinds of email do you send?

I'd expect the response above if you are on a shared mail server or shared IP address.

Less likely but also possibly if you send them too much email too fast to too many bad email addresses.

Do you have your own mail server and a dedicated IP address?
 

jparker

New Email
One server, one SMTP sending from dedicated IP, three small clients. None of these has any bulk mailing or even newsletters. This IP was recently assigned to me, maybe it was abused in the past? It is not on any blacklists, however.
 

EQ Admin

EQ Forum Admin
Staff member
Are you able to get a new dedicated IP to rule out past abuse?

Any forms you fill out pitch yourself as an small ISP smtp relay not a shared mail server.

Any chance you can run two mail servers?

Breaking up your email into high and low quality pools can help. The main high quality pool would be for users sending regular emails with mail programs such as Microsoft Outlook. The lower quality pool would be for users that send to small mailing lists such as small businesses sending to <1000 recipients. It could also be sued for outgoing email from web forms and other web site generated emails.

The more you can do to separate the junk from the good the better chance you'll have of getting the good email into Yahoo inboxes.
 

EQ Admin

EQ Forum Admin
Staff member
Which MTA do you use? Does your internet connection provider have smtp relays? If they do you could try configuring your mail server to relay destined for Yahoo through their smtp relays and not direct to Yahoo from your mail server.
 
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