RE: [exim] Is there and logical reason to reject mail from: …

On Wed, 13 Oct 2004, David Brodbeck wrote:

> There's also no valid excuse for sending mail with an empty return
> path to a mailbox that is never used as an envelope sender.

Agreed. However, if we became aware (by whatever means[1]) that you
repudiated a bounce to postmaster at the RCPT stage, you might well
land up in our "unreachable domains" blacklist, meaning that we'd
neither try to send you mail, nor accept mail from you (except for
postmaster/abuse).

> Assuming postmaster doesn't send mail, any *legitimate* message to
> postmaster would be from a real person, and so would have a valid
> return address.

I know the feeling. We have a whole bunch of role addresses which
exist only to forward mail to appropriate minder(s), and never send
mail themselves. They get pestered with spam rejection reports for
spam that they never sent.

But you better reject null-sender transactions later than the RCPT
phase, I'd say.

good luck

[1] We don't blindly attempt callouts to verify senders, but we do it
selectively; and of course sometimes the postmaster tries a callout by
hand if there seems to be some kind of problem.