So, I set up a brand new Mailinabox, and while testing it on Desktop Mac Outlook (ie the program, Outlook for Mac) it would not really do any autodiscovery of configurations. I basically kept erroring out. It works fine on iOS, and configures itself just fine.
I tried it with both the ‘Microsoft Exchange’ setting, as well as the Outlook.com setting (I don’t really expect Outlook.com to work), but shouldn’t the ‘Microsoft Exchange’ setting work properly? Again, this is on the Mac version of the Microsoft Outlook application.