Split from this thread.

I too am having problems with emails not sending from my Windows Live Mail account.  The error message I am getting is :

The message could not be sent because the server rejected the sender's email address.

Server Error: 530
Server Response: 530 Authentication Required (VM401)
Server: 'smtp.ntlworld.com'
Windows Live Mail Error ID: 0x800CCC78
Protocol: SMTP
Port: 25
Secure(SSL): No

Not sure what I need to do to make my outgoing server require authentication.

Hope you can help.