I'd like to know a common way to configure "transport settings" properties in Exchange 2007. More specifically I would like to hear how to configure the option "enter the DSN codes. DSN messages that have these DSN codes will be forwarded to the Microsoft Exchange Recipient" on the tab "message delivery".
For some reason we are not receiving DSN messages when we mail something to users in other companies that don't exist. I think it might be cause the above setting is configured badly.
Right now I have only the following codes in that setting :
Or is there a way to enter all possible DSN codes ?