I've been given an Exchange 2013 server to use in a separate forest, but on the same IP network as another forest. On my forest I have Exchange 2013 with a DC/DNS installed on it.
Exchange itself works fine, but I'm trying to set it up to use external DNS in the forwards on the WAN interface, but when I changed it, all of my inbound e-mail stopped. The queue viewer showed the following error: #554 5.4.4 SMTPSEND.DNS.NonExistentDo
main; nonexistent domain ##
I've attached screenshots of my current settings. The forward screenshot points to a server in the other forest. What can I change up to get external dns going?