SMTP Authentication, often abbreviated SMTP AUTH, is an extension of the Simple Mail Transfer Protocol (SMTP) whereby a client may log in using any authentication mechanism supported by the server.
It is mainly used by submission servers, where authentication is mandatory.
Why does SMTP require authentication?
A “550 Authentication is required for relay” error indicates that your email server requires SMTP authentication in order to send outgoing mail, but the email client used to send email has not been authenticated with your username and password. Fortunately, resolving this error can be done quickly and easily.
How do I authenticate my SMTP server?
Windows® Mail (PC)
- From the Tools menu, select “Accounts”
- Under Mail highlight your Network Solutions E-mail account and click “Properties”.
- Click the Servers tab and make sure that “My outgoing server (SMTP) requires authentication” is checked.
- Click the “Advanced” tab, change the outgoing server port to 587.
What is authenticated SMTP access?
SMTP Authentication is the mechanism by which the clients of an ISP identify themselves to the mail server through which they intend to send email. It is not possible for any person to send email via any mail server they choose; mail servers will only allow the sending of email by legitimate users.
How do I disable SMTP authentication?
Disabling Your SMTP Authentication
Under “Account Settings,” highlight the email account you are using and click on “Change.” Once on “More Settings” screen, go to the “Outgoing Server” tab. Uncheck the box that says “My Outgoing server SMTP.” This requires authentication, so click “OK.”