I can receive mail, but cannot send it

I am receiving the following error message when I try to send mail, receiving
it is fine. All the settings seem fine. I have Vista on my computer

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 xxxxxxxxx Subject 'Fw: failure notice',
Protocol: SMTP, Server Response: '554 Sorry, no mailbox here by that name.
(#5.1.1)', Port: 587, Secure(SSL): No, Server Error: 554, Error Number:
0x800CCC79
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issi