error message using Outlook

When I send via the web-based email client, everything works. But when I send via Outlook, I get an error message:

Your message did not reach some or all of the intended recipients.
Subject: test B from ehome to jwork
Sent: 5/28/2009 12:07 PM
The following recipient(s) could not be reached:
'[email protected]' on 5/28/2009 12:07 PM
550 <[email protected]> No such user here

What's up?

 

Make sure SMTP authentication is enabled in your Outlook settings.

 

It worked. Thanks!

 

You're welcome.