I did try to ask this in a different forum, but was pointed to this one:
This question encompasses a few Microsoft products, but I think this is the best place to ask the question because the actual issue is Outlook 2013 for Windows desktop.
We have Outlook connecting to a couple of different kinds of Shared Calendars. The problem is it is only performing appointment reminders for one of the kinds.
The one that IS working: a shared calendar created by creating a Room on a Windows Phone. When anyone in the Room creates an appointment with a reminder on that calendar, the reminder goes off in each user's Outlook 2013.
The one that IS NOT working: a shared calendar created in Exchange Online. When any member of that shared mailbox creates an appointment with a reminder on that calendar, the reminder DOES NOT go off in each user's Outlook 2013.
The question: How do we get the reminders to work in the second case?