![Thunderbird logo](https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/products/2024-02-12-07-36-53-599028_1.png)
Thunderbird, cannot send emails out.
Error message:
"Sending of the message failed. An error occurred while sending mail. The mail server responded: <ec2-54-219-72-248.us-west-1.compute.amazonaws.com[54.219.72.248]>: Client host rejected: NO THANKS. Please check the message recipient "patrick.gilroy@harmonydesigninc.com" and try again"
Occurs regardless of recipient, whether replying to an incoming email, or composing a new email.