Problem

How do I send non-delivery reports (NDRs) and reject emails to unknown users in MS Exchange 2003?

Solution

This solution is for Exchange Servers 2003. It is assumed your Exchange system is already setup and configured correctly.

In this example we are going to reject emails for unknown users but allow non-delivery reports (NDRs) for existing users.

1. Start the Exchange System Manager
2. Select the properties of "Message Delivery" which can be found under the "Global Settings" folder
3. Select the "Recipient Filtering" TAB
4. Tick the check box labelled "Filter recipients who are not in the Directory" and select OK.
5. Select the "Internet Message From" which can also be found under the "Global Settings" folder in the Exchange System Manager
6. Select the properties of "Standard" in the right pane.
7. Tick the check box "Allow non-delivery reports"
8. Tick the check box "Allow out of office responses". Remember OOO responses are a form of NDR
9. select OK