https://techcommunity.microsoft.com/blog/exchange/updated-exchange-online-smtp-auth-basic-authentication-deprecation-timeline/4489835
https://learn.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/deprecation-of-basic-authentication-exchange-online
https://kyoceradocumentsolutions.com.au/news/oauth2.0-authentication-support
https://www.kyocera-kyosk.co.uk/microsoft-basic-smtp-to-be-disabled/
(Refer to Using Basic SMTP Authentication if not using the OAuth2 Authentication method)
Make sure that Authenticated SMTP is enabled on the Microsoft 365 account.
Make sure MFA is disabled for the account.
Re-authorization is required if the device is restarted for any reason. KYOCERA will address this issue in a future firmware update.
Do NOT do a Connection Test until authorization has been completed
Set SMTP Server Name to smtp.office365.com
Set SMTP Port Number to 587
Set SMTP Server Timeout to 180
Set the Authentication Protocol to OAuth2
Set User Name to <email address>
Set Password
Select Submit to apply the changes
Select Authorize and wait for the Microsoft Exchange Server Authorization page
Select Copy to copy the Code
Select the URL https://login.microsoft.com/device
Paste in the code and select Next
Following any further prompts from Microsoft
The Authorize button will change to Unauthorize if the authorization was successful