There might be several reasons for 550 Sender verify failed’ error when you try to send the email. You may get this error when the sender email account does not exist on the cPanel or the Mail exchange.
For example, you have added a new addon domain or parked domain in your cPanel account and MX records for that domain are set to point a third-party email provider then you will have to configure the email routing through the remote mail exchanger.
Please refer to the below steps to change the remote mail exchanger in cPanel.
- Login to your cPanel account.
- Inside the Email section, click on Email Routing.
- Tick the Remote Mail Exchanger radio button and after that click on change.
That's it now the email routing is set to send email from the third party(remote mail exchange) server.