Hi, I've been having problems with an account that seems to be banned from sending emails although I can still receive them, I get the following error in the bouncebacks:
This message couldn't be delivered because the sending email address was not recognized as a valid sender. The most common reason for this error is that the email address is, or was, suspected of sending spam. Contact the organization's email admin for help and give them this error message.
Generating server: VI1PR07MB4269.eurprd07.prod.outlook.com
Remote server returned '550 5.1.8 Access denied, bad outbound sender AS(42004)'
I'd be grateful for any assistance in this matter.
