Or: letting my wife see my personal calendar.

So yes, I keep all my personal calendar items in the totalnetsolutions.net O365-hosted account calendar. But that doesn’t stop our family from having the calendar sharing problems that apps like GetClockwise https://www.getclockwise.com/ Cozi https://www.cozi.com/ or even shared Google or iCloud calendars try to solve.

The problems we ran into with Cozi were that we had to actually put the items there, then subscribe to the Cozi calendar from everywhere, when most of the time i’m looking at a calendar, I want to look at a single calendar. Can I agree to host this PTO event, or is my wife going to be out of town? Seeing the free/busy from her calendar, my calendar, etc. in one place got difficult.

So I went back to basics: Exchange can publish free/busy data. If everyone is an O365 subscriber, can’t we just share cross-organization? And the answer is that yes we can… IF the organization allows it! Since I am the admin for the TNS organization, I can share my calendar out, and not have to forward events everywhere. here’s how:

First, the admin has to follow the steps here: https://docs.microsoft.com/en-us/office365/admin/manage/share-calendars-with-external-users?view=o365-worldwide – Log into the Admin Center, click “Show all”, then “Settings” and finally “Serivces & add-ins”. The list of add-ins will change (as of today it includes Azure MFA, Calendar, Cortana, Directory Synchronization, and a host of other services), but you’re looking for “Calendar”. Click that and you’ll get this pane slide in from the left:

O365 Admin Center Calendar Sharing Settings

Click “Let your users share their calendars with people outside of your organization who have Office365 or Exchange” and “Save Changes”.

BUT WAIT, THERE’S MORE! Now click “Go to the Exchange admin center to manage additional settings”, and click “organization”:

O365 Admin Center Organization Sharing page

From here, under the “individual sharing” section you can create a new policy (which has to be assigned to users), or hit the pen to edit he “Default Sharing Policy” and get this page, where you can add the domain you want, and the amount of data to allow users to share (up to and including):

O365 Sharing Rule for Default Policy

Once that’s shared, you can save everything and log out. Now it’s up to the individual users to follow the settings here:

https://support.office.com/en-us/article/share-your-calendar-in-outlook-on-the-web-7ecef8ae-139c-40d9-bae2-a23977ee58d5#bkmk_beta

But realize that private events will NOT be visible in a shared calendar view. You’ll be able to load the free/busy data when scheduling, but not see the events in an overlay, even if you allow greater organizational sharing (as I have in the screenshot above). Since my wife’s work, and my BeyondTrust work are both O365 tenants, I was able to share more-relaxed versions of my calendar with both organizations, send to the individual email addresses, and now we can see synchronized calendar overlays in our own work Outlook calendars.