We having issues receiving mail in Exchange 2016.
We use a smart host to deliver mail to our Exchange 2016 server via port 25.
By means of the "Default Frontend" receive connector in Exchange.
Basic authentication is enabled, as well as Anonymous Users permissions group.
Scoping is the local IP of the smart host.
Mail is piling up in the smart host queue.
Receiving mail was working fine up to a recent power failure.
During troubleshooting, I found no authentication username & password configured in the smarthost.
Can a receive connector in Exchange receive mail from a smarthost via SMTP without authentication?
The smart host logs does not show any specific error related to Exchange not receiving the mails.
Using an Exchange mailbox to authenticate, should I use the format email@example.com as the username to authenticate?