https://www.godaddy.com/en-uk/help/enable-smtp-authentication-40981
Turn on SMTP Authentication to send email from multifunction devices (like printers and scanners), apps or reporting servers.
smtp authenticationenablemicrosoftgodaddyhelp
https://mailtrap.io/blog/smtp-auth/
SMTP authentication protects your mail server from unauthorized use. Learn more about SASL mechanisms, ports, and errors associated with SMTP AUTH.
smtp authenticationmailtrap bloghandle
https://support.microsoft.com/en-us/topic/smtp-connection-fails-when-you-log-on-with-a-child-domain-account-and-use-ntlm-authentication-in-exchange-server-2013-91281eef-aad2-7c58-8ab3-92fba00ffe7f
Fixes an issue in which the NTLM authentication fails in an SMTP session when the UserPrincipalName property of the authenticating user references a child...
smtpconnectionfailslogchild
https://www.godaddy.com/en-ca/help/enable-smtp-authentication-40981
Turn on SMTP Authentication to send email from multifunction devices (like printers and scanners), apps or reporting servers.
smtp authenticationenablemicrosoftgodaddyhelp