wont send windows mail: heres the message

[mike]

The message could not be sent. The authentication setting might not
be correct for your outgoing e-mail [SMTP] server. For help solving this
problem, go to Help, search for "Troubleshoot Windows Mail", and read the
"I'm having problems sending e-mail" section. If you need help determining
the proper server settings, please contact your e-mail service provider.

The rejected e-mail address was . Subject 'BitTorrent - Free software
downloads and software reviews - CNET Download.com', Account: 'shawmail',
Server: 'shawmail.wp.shawcable.net', Protocol: SMTP, Server Response: '550
#5.1.0 Address rejected (e-mail address removed)', Port: 25, Secure(SSL): No,
Server Error: 550, Error Number: 0x800CCC79

 

[PA Bear [MS MVP]]

Is (e-mail address removed) your email address?

Have you ever been able to Send with those settings from that account?

Are you connected to the internet via shawcable.net when sending?

 

[Gary VanderMolen \(MVP\)]

I tested that address (e-mail address removed), and it also failed for me.
Are you able to send to other recipients, including yourself?