Vista - Eamil Account

I am trying to set up another account in outlook, I keep getting the error:
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 'popper130@xxxxxx'. Subject 'Hi',
Account: 'pop-server.tampabay.rr.com', Server: 'smtp-server.tampabay.rr.com',
Protocol: SMTP, Server Response: '550 Invalid recipient:
<popper130@xxxxxx>', Port: 25, Secure(SSL): No, Server Error: 550,
Error Number: 0x800CCC79

I have followed the easy instructions, but will still not work. I have the
correct incoming & outgoing mail server descriptions?

Hello.

This tutorial addresses many issues with Windows Mail. It be helpful to you. Here's the link: Windows Mail problems

"mello" <mello@xxxxxx> wrote in message
news0F8728D-7BB4-4C4C-9E04-3011D21D1E28@xxxxxxIt looks like you're getting an error message from Windows Mail, not
from Outlook. Are you sure which program you're using?

Also the error message appears to say there is no one with that
email address. Can you contact the person you are trying to
send that message to by some other means and ask if the email
address is correct?