I think one reason for bounces could be that the mailman mailing list does not handle DKIM properly. When a user sends a mail to the list, it passes through the DKIM signature, but it also modifies the mail (adding a standard footer as the mimimum, probably more) As a result, the DKIM signature of messages received via the list is invalid, and maybe some mail servers see it as a reason to reject the mail (as if it is spoofed). In my mail system, most mails in this list get a red color because that is what some rule processing here does to get my attention to falsified mails.
In fact this should be solved by mailman, but some googling seems to indicate that the mailman people know that, but have not yet come into action. So likely there is no setting in the admin panel to easily solve this. Maybe some extra software or feature of the existing software could be used to work around this. That would at the minimum have to delete any DKIM-Signature: header on incoming mail (unfortunately this is a multiline header so it will require more than passing through some simple grep or sed), and additionally it could add a new DKIM signature afer all mailman processing, for the mailman.ampr.org domain. But the latter is optional.
Rob
On 7/29/21 10:27 PM, Thomas Osterried via 44Net wrote:
Hello Chris,
Am 29.07.2021 um 22:13 schrieb G1FEF via 44Net 44net@mailman.ampr.org:
Hi Thomas,
I can see that the mailing list software put you on moderation due to excessive bounces, that’s the reason.
thank you for your info.
But I havn't any e-mail problem. Unfortunately, two months are a too long time for looking at logs. Do you have such a bounce mail?
vy 73,
- Thomas dl9sau