SMTP Error (550): Failed to add recipient.

SMTP Error (550): Failed to add recipient

While sending email from webmail, I was getting the below error :

SMTP Error (550): Failed to add recipient “xxx@gmail.com” (Verification failed for <xxx@xyz.net>
The mail server could not deliver mail to xxx@xyz.net. The account or domain may not exist, they may be blacklisted, or missing the proper dns entries.Sender verify failed).

All DNS seems fine but still getting above error.

Solution :

1. Check if the MX record for the domain “xyz.net” is valid or not.
2. If MX record is pointing to same server (local) then change Email Routing to : Local Mail Exchanger.
3. If MX record is pointing external server (remote) then change Email Routing to : Automatically Detect Configuration