Symptom
Attempting to email from within MIP and getting an error message while using an on-premise exchange server that is in a different network location.
The SMTP Server requires a secure connection or the client was not authenticated. The server response was: 5.7.1 SMTP; Client does not have permissions to send as this sender.
*You will also see that sending a test email from the Global Admin email will work but changing the “Send From” email address to a user’s email address will not work.
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