[Mailman-Users] rejecting messages *to* non-members

Mark Sapiro mark at msapiro.net
Thu Nov 26 02:18:15 CET 2009

glen martin wrote:
>I've got some rude users who occasionally cc non-list members on their 
>messages to a restricted list that is actually intended to be private 
>(membership by invitation only).  Then, as you might expect, when the 
>non-member replies, that message is rejected or held for approval.  This 
>doesn't seem friendly.
>The root cause, though, is my users.  I'd therefore like to train them 
>:) by rejecting their posts that copy non-members.
>A natural spot for such an option would seem to be in Recipient filters, 
>but I don't see anything there, nor in the rest of the options for that 

Actually, the best you can do is Recipient filters. If you set
require_explicit_destination to Yes and max_num_recipients to 2, any
post which is not explicitly addressed to and only to the list will be

I.e. the list (or an acceptable alias) must be an explicit recipient or
the post will be held for implicit destination, and if there are 2 or
more explicit recipients, the post will be held for too many

If you want more such as rejecting rather that holding the post and
accepting other explicit recipients as long as they are list members,
you will need a custom handler (see the FAQ at

Keep in mind that whatever you do may be futile. If the 'rude' members
are insistent, they will quickly learn to Bcc: their non-member
recipients, and there's no way you'll even see that, at least until
the Bcc'd non-members reply.

Also, list members with more than one email address may legitimately
Cc: one of their other addresses that isn't a list member.

Mark Sapiro <mark at msapiro.net>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan

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