[Mailman-Users] AOL screening Reply-To header thru DMARC ?

[John Levine]

>I have a somewhat different issue. I am using dmarc_moderation_action =
>Munge From, and when an AOL user posts to the list, the list message
>sent back to the user bounces with "521 5.2.1 :  AOL will not accept
>delivery of this message. (in reply to end of DATA command))". The same
>messages sent to other AOL users are accepted by AOL.

If you're munging with .INVALID or the like, I have observed that AOL and
some other ISPs now refuse mail if the From: domain doesn't resolve.
I've changed my hack so it now append a suffix that does resolve (I snagged
dmarc.fail) and overimplemented it so the munged addresses actually work.

I would be surprised if AOL were doing DMARC checks on Reply-To, and agree
that it's not a problem worth solving.  But I'll ask around.

R's,
John