Recently I’ve configured a client’s hosting to point its MX to an external Spam Filter. After pointing to the new MX server, I started receiving the following errors:-
lowest numbered MX record points to local host
and
Please turn on SMTP Authentication in your mail client.
After research, it seems that I’ve configured the Cpanel Email Routing wrongly.
Solutions
- Email Routing needs to be set to Local instead of Remote even though the MX IP is not local to the server.
- The domain name needs to be set inside the file /etc/localdomains. (By right once you set Email Routing to Local, the domain name should be automatically inserted into the file. In my case, it did not. I’ve to manually insert it in.)
Solution #1 did the trick for me. Thanks a lot for your post, really helpful