Here are some steps to help fix email server errors:

1. Check if the email server is connected to the Internet.
2. Verify that settings, such as domain, port, and authentication are correct.
3. Check if the server is offline and whether it is the cause of the problem.
4. If the server is not responding, restart the server to see if that resolves the issue.
5. Check all the protocols and firewall rules for the server.
6. Check the server logs to help debug any underlying issues.
7. Contact your server administrator if the issue persists.