Recently, I got my office365 account and found it surprisingly difficult to configure it with mac OSX Mail app. There were numerous inane outdated tutorials and documentation. Finally it came down to a simple configuration which worked on
OSX Yosemite and higher.
- Open mail
- From the top menu, select add account
- Click on Exchange and add an Alias (name with which you want to refer the account), email and password of your office365 account
- Mail will try to access your account but will fail and show you a new form
- Add the url: outlook.office365.com
- Voila! Mail will be able to connect seamlessly
Hope this helps someone!