Yahoo introduced a feature (DMARC) this week that basically says "If a message has a yahoo.com email address as the FROM address, and it didn't come from a Yahoo.com server, then it's not acceptable." This is causing a LOT of problems with our customers' Mailman mailing lists.
You can read more about it here: Yahoo email anti-spoofing policy breaks mailing lists | PCWorld
When a Yahoo.com user POSTS to the list, many email providers are respecting Yahoo's DMARC record and BOUNCING the list messages back to the server, which is causing many non-Yahoo users to get unsubscribed or at least have their subscriptions disabled.
A typical bounce might look like:
What is the solution? It appears that Mailman introduced a work-around for DMARC with Mailman version 2.1.16. See the changelog: https://launchpad.net/mailman/2.1/2.1.16
I'm hopeful this new feature will solve the problem... otherwise the only other solution is to remove all yahoo.com subscribers and have them resubscribe using a different email address.
Hope this helps!
- Scott
You can read more about it here: Yahoo email anti-spoofing policy breaks mailing lists | PCWorld
When a Yahoo.com user POSTS to the list, many email providers are respecting Yahoo's DMARC record and BOUNCING the list messages back to the server, which is causing many non-Yahoo users to get unsubscribed or at least have their subscriptions disabled.
A typical bounce might look like:
Code:
2014-04-12 22:18:17 1WZAvw-0008FY-BO ** [email protected] R=dkim_lookuphost T=dkim_remote_smtp:
SMTP error from remote mail server after end of data: host mta6.am0.yahoodns.net [98.138.112.34]:
554 5.7.9 Message not accepted for policy reasons. See http://postmaster.yahoo.com/errors/postmaster-28.html
WHM 11.42.1 upgraded Mailman to 2.1.17, so the feature should be there. I use the STABLE tier, and 11.42.1 hasn't made it to STABLE (as of the day I am writing this) so I have not had a chance to try the feature... 11.42.0 still has 2.1.15, thus I don't have access to the new feature yet.There is a new list attribute from_is_list to either rewrite the From:
header of posts replacing the posters address with that of the list or
wrap the message in an outer message From: the list for compatability
with DMARC and or ADSP. There is a new mm_cfg.py setting
DEFAULT_FROM_IS_LIST to control the default for new lists, and the
existing REMOVE_DKIM_HEADERS setting has been extended to allow removing
those headers only for certain from_is_list lists. This feature must
be enabled by setting ALLOW_FROM_IS_LIST to Yes in mm_cfg.py. See the
description of these settings in Defaults.py for more detail. This
feature is experimental in 2.1.16, and it is subject to change or to
become just one of the two methods in a subsequent release. People
interested in this feature are encouraged to try it and report their
experiences to the [email protected] list.
I'm hopeful this new feature will solve the problem... otherwise the only other solution is to remove all yahoo.com subscribers and have them resubscribe using a different email address.
Hope this helps!
- Scott