Posted to the list as well - added info here for those that are forum centric.

Finally got it to behave with version 4.62 and an outgoing rule filter. I

do use the interface to create my rules and somewhat condensed what each

entry does so that it didn't line wrap terribly in my post(s).

I use Mercury/32 as my gateway and it forwards to internal servers. Because of this configuration, messages sent to invalid accounts (i.e. former staff) will process thru Mercury but get a "550 No such recipient" error (using MercuryE) when attempting to deliver to the internal servers. LDAP used to take care of this on external connections to Mercury/32 (forced to move from Pegasus Mail).

Is there some way to return to sender, filter, delete or discard those messages as I know for certain that they aren't to valid addresses? I am not interested in keeping up aliases or synonyms as this is a duplication of administration (all user accounts already configured on second server).

[quote user="bryroller"] Is there some way to return to sender, filter, delete or discard those messages as I know for certain that they aren't to valid addresses? I am not interested in keeping up aliases or synonyms as this is a duplication of administration (all user accounts already configured on second server).[/quote]

What happens to them at the moment?  I would expect them to generate a delivery failure message (which can be stopped by removing the template), but I'm not sure what you really want to do with them.

Are some of them spam? if so, you won't want to return those to 'sender' as that would be backscatter.

A little more info on your setup would be useful too.

Thanks for your response. I'll first better describe my setup.

I have Mercury/32 with MercS receiving mail for two domains. ClamWall and SpamHalter are running on Mercury/32 and they are very effective. I use the MercuryFoward v 0.03 daemon to "push" those messages to another internal (to the firewall) mail server via MercE.

When the internal [second] mail server receives a message for an account that doesn't exist, it returns a 550 error to MercE and I receive the delivery failure messages from Mercury/32 (I am the designated postmaster).

So... everything is working as it should but being a school, students graduate, transfer, withdraw and the mailing lists that their teachers / counselors have them sign up continue to deliver messages. When the students don't unsubscribe (99% of the time), these type messages end up failing delivery and come to me.

What I'd like is to not have messages sent from MercE to the second mail server get returned to me when the account doesn't exist (when the second server generates a 550 error).  Can you assist me in a rule that would discard (and maybe return) the messages that are addressed to a non-existing account. I am not too worried about backscatter since most of these senders are legitimate.

Any help you can provide will be much appreciated.

I see Thomas has replied on the mailing list anyway. :)

I assume that Mercury accepts all mail for your domains, regardless of local address.  All I can think of as alternatives are:

1) use filtering in your email client to process these undeliverable errors - discard or whatever

or 2) use a different account for the postmaster so that the emails don't end up with you - but have some means of checking that account on a regular basis

Mercury does accept all mail, regardless as you suspected.

I had an idea but it isn't working - I tried an outgoing rule that goes like this:

Headers  From [Contains] postmaster@MyDomain.org [Action] Logical AND

Headers To [Contains] MyAddress@MyDomain.org [Action] Logical AND

Headers Subject [Contains] Postmaster Notify: Delivery Failure. [Action] Logical AND

Expression Received: *by mta2.MyDomain.org* (Headers only) [Action] Logical AND

Expression  *550 No such recipient* (Body only) [Action] delete message

Can rules work upon postmaster delivery failures? The above rules are ignored completely...