I getting the following error while I am taking SMTP test.
The SMTP server does not accept mails to postmaster@[IP_ADDRESS]. This is a very bad thing, as this address is used by people that don't know your domain name! The reported error is:
550 Requested action not taken: mailbox unavailable or not local
Is it really possible to create an email address with IP address not domain? Or do it have any other meaning? Please tell me how can I fix this error.