Bouncing messages from users@global.libreoffice.org

From time to time I receive messages of the type above, but never any
information about what I am expected - or allowed - to do with the «list of
bounced messages» which accompanies them. Can anyone on the forum enlighten
me ?...

Henri

Hi Henri,

I also had the same message and note that it was for the same message number that was ‘missed’. As I am sure we are not using the same ISP in South Africa, so who knows maybe the mailing list admins picked it up as spam. ANYONE know??

Regards
Hylton
ISP: Voxtelecom

I think I do.

The list help text says "Anyone can retrieve message number N from the list's archive by sending a message to <users+get-N@global.libreoffice.org> (change the N to the number
of the desired message)". But if I'm right, any repeat copy would also fail to be delivered to you.

It's all down, I think, to DMARC; see https://en.wikipedia.org/wiki/DMARC . This is a well-intentioned scheme to allow mail providers to reject incoming messages if they originate from a mail server which is not a registered server for the domain in the From: header. Such messages will generally be spoofed and thus spam, so this is a Good Thing. But a problem arises if mailing list processors (quite sensibly) preserve the original From: address on forwarded messages - as does the LibreOffice Users list processor. The forwarded message claims to be from the original sender (which it is, of course), but is injected into the LibreOffice mail server, which gives it the appearance of being a spoof message. You will fail to receive such messages if both (1) the originating mail domain publishes a list of approved servers and requires receiving systems to reject messages from elsewhere, and (2) your mail provider chooses to play ball and obey this requirement.

My mail domain (which is Yahoo in disguise) satisfies condition (1), so you will fail to receive my messages to the list if your mail provider satisfies condition (2). I do not receive copies of my own contributions. Message 55635 is, I think, my contribution to the thread "full date string to date"; you can see this at
http://document-foundation-mail-archive.969070.n3.nabble.com/full-date-string-to-date-td4271380.html . If I'm right, you will not receive copies of this message via the list, which is why I'm copying it to you both directly.

There are solutions to this problem, the simplest of which is for the list processor to append something such as ".INVALID" to the From: address in relevant messages, so that they are no longer recognised as coming from a DMARC-conformant domain. Many mailing list providers do this. I wrote to <postmaster@documentfoundation.org> about this as long ago as 1 May 2018, but my suggestion for action was rejected, on the ground that "none of the workarounds [are] satisfactory for everyone". Thus the problem continues ...

Brian Barker