Select Edit/Accounts and then Add / Mail account. Do not select the "Look up mail server details" button. It won't work.
Change "Server type" to "Exchange Web Services"
Useas Host URL.
Click On Authentication, click the box "Override Office365 OAuth2 settings. Use " and use 20460e5d-ce91-49af-a3a5-70b6be7486d1 as Application ID.