NDR – Undeliverable
Q: I received an NDR that says "Undeliverable: Sorry the email could not be delivered. The user firstname.lastname@example.org does not exist or is not authorized to use this forwarder."
A: When adding users to the Add Users screen - be sure you don't include the domain name. For example: if the user's email address is email@example.com - only "Jon" should be entered.