Why Office 365 add-in is disabled in Windows but not in Mac in Shared Calendar?

Question

We have built an add-in that works on Outlook Calendar. Now, that we want to explore delegate module, we have started exploring our options in Shared Calendar access.

Without any changes made to the add-in as of now, we see an inconsistent behavior in shared calendars. The add-in gets disabled in a shared calendar in Windows and works fine on Mac. Although we have not yet started coding the functionality that would work as per the selected calendar, why do we see the inconsistency between the platforms? Which one is the correct behavior - the Windows one or the Mac one? If at all there will be a fix from Microsoft, what would that be - enable for Windows or disable for Mac?

Microsoft suggests this workaround:

https://support.office.com/en-us/article/office-add-ins-aren-t-available-from-a-shared-calendar-0f46450c-b011-40cc-a077-9dc59014937b#ID0EAABAAA=Outlook_2016,_2013

I cannot expect users to switch between client and web. Also, it's weird that it is disabled in Windows. Microsoft owns both Outlook and Win, but let it work for Mac - just an observation.

Both are Outlook 16 with Office 365 cloud.

Answer 1

Well, depending on how your add-in works, it may be be course Outlook for Mac and Outlook for Windows builds on two different ways to communicate with the Exchange servers.

Outlook for Windows is build on MAPI where Outlook for Mac is build on EWS.

You could also check this reference table for some of the difference between Outlook for Mac and Outlook for Windows

Answer 2

Thanks for reporting the issue. We are working to fix this for outlook on mac.