Re: Office 365 Calendar support for macOS Calendar App

[Mark Tinka <mark@tinka.africa>]

Thanks, all, for the replies.

After speaking to Kovich in unicast, I realized I needed to explain the 
issue in more detail.

When we ran Exchange on-prem or in the cloud, there was no issue running 
macOS's native Calendar app with it. However, when we moved to the 
Office 365 cloud service, it is a whole other affair with how Microsoft 
offer that service compared to their generic/previous cloud Exchange.

With Office 365, non-Microsoft apps have to be pre-approved by 
Microsoft, at which point they can be loaded into the master profile for 
your enterprise account with them, e.g., Thunderbird, e.t.c.

This all became necessary after Microsoft (and other cloud providers) 
deprecated/favoured "Normal Password" authentication for OAuth2 
authentication. In Microsoft's case, it was a full-on deprecation.

Google have the same feature for their cloud services, something they 
call "Less secure apps". However, Google seem to be more generic about 
allowing non-Google apps to access their cloud vs. Microsoft who need to 
pre-approve 3rd party apps that you can add to your enterprise profile. 
Well, at least as far as I can tell.

Microsoft call it "Admin Consent", or something like that:

https://learn.microsoft.com/en-us/azure/active-directory/manage-apps/configure-admin-consent-workflow

Thunderbird, and as far as I can tell, iOS in general, are supported. So 
I can use Thunderbird to read e-mails hosted by Office 365, because that 
is a 3rd party app Microsoft support and that your 365 admins. can 
authorize. There are a ton of other 3rd party apps Microsoft support on 
365 from a multitude of other developers.

However, macOS's native Calendar app is not one of them. This surprises 
me, which is why I reached out.

A link of what pops up on the macOS Calendar app (and other 
non-Microsoft apps), looks like this:

https://ibb.co/XtvfpJ8

I realize that how Office 365 works on the back-end is probably foreign 
to a lot of people (I know it is for me), but hopefully there is one 
person here that knows enough about this to point me in the right 
direction, as our own 365 admins. are stumped.

Mark.