Exchange 2003 unexisting recipients queued

[jaxone]

Hello.

We are running Exchange 2000 / 2003 on a network with 800-1000 users.
We are receiving e-mails for 10-15 domains.
Some of the users receive email for 2 or 3 of this domains , some of them
have one , some of them for all.
All the incoming E-mails are managed by a smtp server on the DMZ and
forwarded to one of our Exchange servers that will distribute them
internally.
For outgoing mail we use one of the exchange servers that will send out the
e-mails directly.
All our domains have one MX record that is the SMTP server on the DMZ.
Now , the SMTP server accepts all e-mails for all the domains. Once arrived
on the Exchange servers the mails with the existing recipients are delivered
to the respective mailboxes.
The e-mails for non existen recipients are just queued on the exchange
server and then when the delivery time expires they are just dropped.
How can I get rid of this queuing process as the e-mail addresses are not
existent actually.
For example let's say we receive mails for : abcd.com and xyz.com
I have an user that has only one mail address : user1@abcd.com
If an E-mail is sent to user1@abcd.com the mail is delivered fine but if the
mail is sent to user1@xyz.com then the e-mail is just queued .... why ? Why
does the Exchange not generate a NDR right away and drop the message ?
I have enabled "Recipient Filtering" and filtered the reciepients that are
not on Active Directory on our Exchange 2003 server (the one that is
distributing the mail) but the mails are still queued !!

Any ideea how to solve the problem or where is the configuration mistake ??

 

[pschwarz]

Not sure if this will provide the solution, but perhaps a "catch-all" account

http://support.microsoft.com/?id=324021

 

[xmsre]

The catchall will dump all mail for a specific domain in a single mailbox; I don't thing the user will appriciate that. What would work is a third party product that allows you to send all emails with unresolved recipients to a specific mailbox with no ndr. Mailcatcher comes to mind. The "specific mailbox" can be a DG with no members [black hole] or a mail enabled public folder with a short age limit [a little insurance just in case there were connectivity issues between exchange and the GC; we wouldn't want to black hole everyone's email just because a GC went down for a short period].

http://www.luninfo.com/mailcatcher.asp

XMSRE