Not able to send user registration mails to new users.
The email failed to send. Please contact the Forum Administrator with the error message below.
Server Error Message:-
The server rejected one or more recipient addresses. The server response was: 550 Authentication is required for relay
Visit your domain cPanel (hosting cPanel) now look under mail section you will find “MX Entry”. Now in it the email routing setting should be “Local Mail Exchanger”, once you click this option, click “change”.
In outlook you have to do following steps :
You have to Enable SMTP Authentication in your pop3 application.
First open Outlook application and visit :
Tools >> Accounts >> Click the Mail Tab >>Double Click your Fast2host POP3 Account
Click the servers tab >>Then right at the bottom, put a tick next to “My outgoing server requires authentication”.