While I was doing choir mailing list maintenance —deleting spam, that is; this is the small list on which I know everybody personally, not the big sprawling list with lots of members who tend to forget which of their accounts they’ve subscribed from— I noticed several messages purporting to come from the list itself. Now the list never sends anything by itself, it’s just a forwarding service for members’ messages, so any message from the list rather than a person must be spam. I thought I’d save myself some trouble, so I added the list address to the “Discards” filter.
Apparently, it’s not a “discard silently” filter. Every message it throws away, it notifies me of. And I get it in my mailbox with several layers of wrappers.
- The spam handler notices that the message is in HTML and has some other points-scoring characteristics, and marks it as spam. It encapsulates it and sends it on to koor@valdyas.org, which is handled by Mailman.
- Mailman knows that I’ve told it to discard anything from koor@valdyas.org and obligingly does so, sending koor-owner (who is me) an auto-discard notification with the message encapsulated.
- The spam handler catches the auto-discard notification and notices that it’s mostly in HTML etcetera, and marks it as spam. It encapsulates it and sends it to koor-owner, that is, me.
- The spam handler catches the message and notices… well, yes, that, and marks it as spam. It encapsulates it and sends it on.
I don’t know how to turn auto-discard notifications off yet, but I intend to either find out or find the filter and edit it, because this is more hassle than just telling Mailman to “discard all messages marked Defer” with a few more messages to discard.
ETA: disabled auto-discard notification for both lists, and also uncaught bounce notification even though Mailman recommends against it, because I’ve never seen an uncaught bounce —even on the big list— that was anything other than a spammer’s attempt to get an answer.
I don’t really understand the last embedding: it seems to have gone through the spam handler twice. But it’s not the first time I’ve had the extra layer of encapsulation. Four is extreme, though.