2010 Catch All (despite better judgement)

Hi there,

I have a client who we are migrating from SBS 2003 -> SBS 2011

In Exchange 2003 they currently have it set up so that all mail addressed to invalid recipients goes to “[email protected]”

I normally don’t like catchall mailboxes, however they want it set up. The Exchange server isn’t directly exposed to the Internet and runs through a spam filtering relay so hopefully most spam will get killed before it gets through.

So far, I have tried a transport rule as follows:

Apply rule to messages
from users that are ‘Outside the orgranization’
redirect the message to ‘[email protected]’

The bit I am having trouble with is the exception. If I use “except when the message is sent to a member of” and set it to “All Users” then the rule does nothing and mail with bad addresses gets bounced. If I set it to the domain universal distribution list then absolutely everything gets copied to the catchall mailbox, even messages for valid users.

I have disabled recipient checking on the hub transport anti-spam section.

The technet article says to manually exclude each email address which is a logistical nightmare. Not to mention it is easy for first level support to forget when they deal with many clients.

So, anyone know of a simple exclusion that works?