how to set up authentication

To: mutt-users@xxxxxxxx
Subject: how to set up authentication
From: zirath <zirath@xxxxxxxxxxx>
Date: Mon, 20 Oct 2008 03:07:11 -0400
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I'm getting an error message when trying to send mail externally (thruour dsl isp's server) that authentication is needed.

Would appreciate information on how to set up the user name and passwordfor this.


Thanks.