The message could not be sent because the server rejected the sender's email address. The sender's email address was *** Email address is removed for privacy ***'.

Subject 'test'
Server Error: 530
Server Response: 530 Authentication Required (VM401)
Server: 'smtp.blueyonder.co.uk'
Windows Live Mail Error ID: 0x800CCC78
Protocol: SMTP
Port: 25
Secure(SSL): No

and

Unable to send or receive messages for the Blueyonder.co (tonybone) account.

Server Error: 3219
Server: 'https://mail.services.live.com/DeltaSync_v2.0.0/Sync.aspx'
Windows Live Mail Error ID: 0x8DE00005