Thanks. Looking at one of the notifications, I see this is a DKIM failure.: The response from the remote server was:
550 5.7.9 This mail has been blocked because the sender is unauthenticated. Yahoo requires all senders to authenticate with either SPF or DKIM. Authentication results: DKIM = FAILURE - SPF XXX.org with ip X.Y.Z.W = SUCCESS. See https://senders.yahooinc.com/smtp-error-codes/#authentication-failures for more information. This has worked for a long time. What would suddenly cause DKIM failures? On Thu, May 7, 2026 at 11:02 AM Paul Tomblin via Mailman-users < [email protected]> wrote: > The first thing I’d do is look at the outgoing mail logs. If it’s bouncing > 1/3rd of your users, it’s very likely it’s one or two whole domains that > are bouncing, probably because your IP has been black listed or you don’t > have DKIM set up right or something like that. The outgoing mail logs might > tell you that. Also, don’t you get a copy of the “disabling bounce”? I > always get one of that when somebody gets bounced off the list. The bounce > message itself usually gives you a clue as well - I think it’s in an > attachment called email.eml or something like that. > > On Thu, May 7, 2026, at 10:39 AM, Stephen Daniel wrote: > > Colleagues -- > > > > I run a small mailman3 server with perhaps 10 lists. All the lists are > > small. > > > > Over the past two days about a third of the users in my most active list > > have been disabled by bounces. I assume the problem is with my setup, not > > with all of those users. > > > > How do I debug this? Can I see the text of any of the bounce messages to > > understand why the emails bounced? > > > > This issue might stem from my running somewhat old software. Currently > > running mailman 3.3.5. > > > > Thanks! > > > > -- Stephen Daniel > > _______________________________________________ > > Mailman-users mailing list -- [email protected] > > To unsubscribe send an email to [email protected] > > https://lists.mailman3.org/mailman3/lists/mailman-users.mailman3.org/ > > Archived at: > > > https://lists.mailman3.org/archives/list/[email protected]/message/F4GUIWJWZYENX2R5G6WIDZLOGR6BOWQG/ > > > > This message sent to [email protected] > > -- > Paul Tomblin > _______________________________________________ > Mailman-users mailing list -- [email protected] > To unsubscribe send an email to [email protected] > https://lists.mailman3.org/mailman3/lists/mailman-users.mailman3.org/ > Archived at: > https://lists.mailman3.org/archives/list/[email protected]/message/RR3TXJOZ42VK3Q3RJYNNPC4KGZ7AAPCX/ > > This message sent to [email protected] > _______________________________________________ Mailman-users mailing list -- [email protected] To unsubscribe send an email to [email protected] https://lists.mailman3.org/mailman3/lists/mailman-users.mailman3.org/ Archived at: https://lists.mailman3.org/archives/list/[email protected]/message/C54XHAFJR2QZUENEIUHCCCTOJTUQGEXG/ This message sent to [email protected]
