Set Default Sharing Policy for Office 365 Users’ Calendars

You can set the default internal sharing policy for Office 365 user’s calendars using PowerShell. You may decide to set the default for all current users to Limited Details, then add exceptions for users whose calendar is to be kept to Availability (Free/Busy) only.

Here are a few common cmdlets that you can edit and use. See the bottom of this page for a description of the various permission levels.

Set Default Calendar Sharing Permissions for a single user

This example will set the default permission level for the [email protected] user’s calendar to Reviewer.

1. Connect to Exchange Online via PowerShell – See our quick guide for details.
2. Run the following cmdlet:

Set-MailboxFolderPermission [email protected]:\calendar –User Default –AccessRights Reviewer

3. Confirm that it has worked by running Get-MailboxFolderPermission:

Get-MailboxFolderPermission [email protected]:\calendar –User Default

Set Default Calendar Sharing Permissions for all users

1. Open Notepad or Visual Studio Code
2. Copy the following cmdlets and edit as required:

$credentials = Get-Credential -Credential [email protected]
Write-Output “Getting the Exchange Online cmdlets”

$Session = New-PSSession -ConnectionUri https://outlook.office365.com/powershell-liveid/ `
-ConfigurationName Microsoft.Exchange -Credential $credentials `
-Authentication Basic -AllowRedirection
Import-PSSession $Session

foreach($user in Get-Mailbox -RecipientTypeDetails UserMailbox) {

$cal = $user.alias+”:\Calendar”

Set-MailboxFolderPermission -Identity $cal -User Default -AccessRights LimitedDetails

}

3. Save the file as a .ps1 PowerShell Script file. This is what it’ll look like in Visual Studio Code:
4. Open Windows PowerShell.
5. Drag your script file on top of the PowerShell command prompt
6. Enter your Office 365 admin details and click OK

For reference, here’s a list of the Access Rights roles and descriptions for the permission levels of each. See more at: https://technet.microsoft.com/en-us/library/ff522363(v=exchg.160).aspx

Access Rights Roles

Author

CreateItems, DeleteOwnedItems, EditOwnedItems, FolderVisible, ReadItems

Contributor

CreateItems, FolderVisible

Editor

CreateItems, DeleteAllItems, DeleteOwnedItems, EditAllItems, EditOwnedItems, FolderVisible, ReadItems

None

FolderVisible

NonEditingAuthor

CreateItems, FolderVisible, ReadItems

Owner

CreateItems, CreateSubfolders, DeleteAllItems, DeleteOwnedItems, EditAllItems, EditOwnedItems, FolderContact, FolderOwner, FolderVisible, ReadItems

PublishingEditor

CreateItems, CreateSubfolders, DeleteAllItems, DeleteOwnedItems, EditAllItems, EditOwnedItems, FolderVisible, ReadItems

PublishingAuthor

CreateItems, CreateSubfolders, DeleteOwnedItems, EditOwnedItems, FolderVisible, ReadItems

Reviewer

FolderVisible, ReadItems

The following roles apply specifically to calendar folders:

AvailabilityOnly

View only availability data

LimitedDetails

View availability data with subject and location

Access Rights Permissions

CreateItems

The user can create items in the specified folder.

CreateSubfolders

The user can create subfolders in the specified folder.

DeleteAllItems

The user can delete all items in the specified folder.

DeleteOwnedItems

The user can only delete items that they created from the specified folder.

EditAllItems

The user can edit all items in the specified folder.

EditOwnedItems

The user can only edit items that they created in the specified folder.

FolderContact

The user is the contact for the specified public folder.

FolderOwner

The user is the owner of the specified folder. The user can view the folder, move the move the folder, and create subfolders. The user can’t read items, edit items, delete items, or create items.

FolderVisible

The user can view the specified folder, but can’t read or edit items within the specified public folder.

ReadItems

The user can read items within the specified folder.