The account or domain may not exist, they may be blacklisted, or missing the proper dns entries. (Mail Routing)

Symptoms

When sending mail to a domain on your server, the message fails with the following error:

user@domain.tld is undeliverable: The mail server could not deliver mail to user@domain.tld. The account or domain may not exist, they may be blacklisted, or missing the proper dns entries.

Description

This issue will occur if the domain is not configured with the correct mail routing setup. 

Workaround

If the server is meant to host email for the domain, then the Local Mail Exchanger should be selected.

1. Access the cPanel for the domain as the user.
2. Navigate to "Email / Email Routing"
3. Select the domain you wish to edit.
4. Select "Local Mail Exchanger" and "Change"

If the issue persists, ensure that the MX Records are properly configured:

The account or domain may not exist, they may be blacklisted, or missing the proper dns entries.

Additional Information

How to change the email routing of a domain in cPanel