How to share your default Calendar folder:

1.   In Calendar, in the Navigation Pane, right-click the calendar folder for which you want to change permissions.
2.   Click Change Sharing Permissions. Do one of the following:

Manage access permissions for everyone.

a.   On the Permissions tab, in the Name box, click Default.
b.   Under Permissions, in the Permission Level list, click None to revoke permissions or any of the other options to change permissions.

Manage access permissions for one person.

a.   On the Permissions tab, in the Name box, click the name of the person whose access permissions you want to change.
b.   Under Permissions, in the Permission Level list, click None to revoke permissions or any of the other options to change permissions.

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