I got this error while trying to send a email with Outlook Express. How to fix it ?
The message could not be sent because the server rejected the sender's e-mail address. The sender's e-mail address was '***@*****'. Subject '[*****', Account: 'mail.****', Server: 'mail.****', Protocol: SMTP, Server Response: '550 Access denied - Invalid HELO name (See RFC2821 22.214.171.124)', Port: 25, Secure(SSL): No, Server Error: 550, Error Number: 0x800CCC78.