Microsoft is dropping support for basic auth on Exchange 365. So we're looking into other options for connecting to Exchange. Our Java based app runs as a background service under Tomcat. It monitors and reads from an Exchange inbox.
Is there a way to obtain an OAuth token without using Azure Active Directory?
it won't be retired until at least second half of next year, they are still working on alternative methods per this thread: https://techcommunity.microsoft.com/t5/exchange-team-blog/basic-authentication-and-exchange-online-april-2020-update/ba-p/1275508
but things like EWS will be retired. so its not only about oauth, the legacy endpoints will likely be retired, in favour of graph api if I were to guess. At least for now, if you want to access mailboxes without any user interaction, they are recommending that you use graph api to read email. meaning no, in the future you will HAVEhttps://techcommunity.microsoft.com/t5/exchange-team-blog/announcing-oauth-support-for-pop-in-exchange-online/ba-p/1406600