Email not sending from SAP when using Office 365 email

SAP will not send email out. In looking in the outgoing emails you see that they are not being sent out and have a red X.

The error on the server will include:

The server response was: 5.7.57 Client not authenticated to send mail.

System.IO.IOException: Authentication failed because the remote party has closed the transport stream.

The solution: The IT Team who is handling your SMTP server will need to upgrade the .net. You can follow the Microsoft.com discussion here:

https://docs.microsoft.com/en-us/answers/questions/586487/authentication-failed-because-the-remote-party-has-1.html

The work around: Download the attachments to your computer and then send them out through you email as an attachment.