maybe if you post the complete error message, that will help. Seeing a screenshot of SMTP server settings pane may also help, along with screenshot of incoming server settings pane.

When trying to send a message, the following notice appears:

Sending of the message failed. An error occurred while sending mail. The mail server responded: <martin.peros@bellnet.ca> sender rejected. Please verify that your email address is correct in your account settings and try again.

The settings were checked and all is correct.

Any help would be appreciated.

Thank You.

I am unfamiliar with Bellnet. Have you used this account recently? I ask because most email providers now require security in the setup, but the bellnet.ca website indicates not. You might try normal password, not encrypted. Normally, I would suggest port 587 and STARTTLS, but the bellnet site says not to. My guess is that bellnet may have changed setting requirements and you may need to contact them.