Hi everyone. I have a dedicated Ubuntu box that is running mailman3. I have a single email list on it. The subscriber base is about 350 users. There is a good chunk of these users that are aol.com or yahoo.com users. I've been getting complaints from the Yahoo people that mail is delayed at times, or messages that come out of order.

Looking at the mailq on the box, I can see there are plenty of emails stuck in the queue. I have all sorts of messages like this ...

-Queue ID- --Size-- ----Arrival Time---- -Sender/Recipient------- 3576C540CB4 9917 Tue May 11 11:27:13 pcho-bounces@pchochat.com (host mta6.am0.yahoodns.net[67.195.204.74] said: 452 Too many recipients tnmpmscs (in reply to RCPT TO command)) <removed list of email addresses>

(host mta6.am0.yahoodns.net[67.195.204.74] said: 421 [IPTS04] Messages from 74.112.73.65 temporarily deferred due to unexpected volume or user complaints - 4.16.55.1; see https://postmaster.verizonmedia.com/error-codes (in reply to end of DATA command)) <removed list of email addresses>

10932540D16 32765 Tue May 11 18:34:13 pcho-bounces@pchochat.com (host mta6.am0.yahoodns.net[67.195.228.111] said: 421 4.7.0 [TSS04] Messages from 74.112.73.65 temporarily deferred due to unexpected volume or user complaints - 4.16.55.1; see https://postmaster.verizonmedia.com/error-codes (in reply to MAIL FROM command)) <removed list of email addresses>

(host mx-biz.mail.am0.yahoodns.net[67.195.204.83] said: 421 4.7.0 [TSS04] Messages from 74.112.73.65 temporarily deferred due to unexpected volume or user complaints - 4.16.55.1; see https://postmaster.verizonmedia.com/error-codes (in reply to MAIL FROM command)) <removed list of email addresses>

(host mx-aol.mail.gm0.yahoodns.net[67.195.228.84] said: 421 4.7.0 [TSS04] Messages from 74.112.73.65 temporarily deferred due to unexpected volume or user complaints - 4.16.55.1; see https://postmaster.verizonmedia.com/error-codes (in reply to MAIL FROM command))

(host mta6.am0.yahoodns.net[67.195.228.111] said: 421 4.7.0 [TSS04] Messages from 74.112.73.65 temporarily deferred due to unexpected volume or user complaints - 4.16.55.1; see https://postmaster.verizonmedia.com/error-codes (in reply to MAIL FROM command)) <removed list of email addresses>

So it seems that Yahoo/AOL keeps detecting my mailman3 server as either spam, sending too much email, or too many recipients.

This email server is for our neighborhood community. Its moderated to join, and we know every single user on this list. We know it's not being reported as spam by our users.

Anyone anyone shed some light on how to appropriately solve this issue?