An email account has recently developed a send fault. This account is not the 'default' or main account. The following message is displayed when attempting to send.
The message could not be sent because the server rejected the sender's email address. The sender's email address was .co.uk'.
Subject 'Re: enquiry'
Server Error: 555
Server Response: 555 Refused (external Mail From address). Please enable SMTP authentication to send mail.
Windows Live Mail Error ID: 0x800CCC78