Manage Multiple Calendar Permissions with Exchange 2010 Shell

To edit all Calendars and set Default Calendar permission to Reviewer:

$Mailboxes = Get-Mailbox -ResultSize unlimited
$Mailboxes | ForEach {Set-MailboxFolderPermission $_":\Calendar" -User Default -AccessRights Reviewer}

Note:

• Use different Set-MailboxFolderPermission cmdlets when using Outlook in different languages (English, Dutch etc).
  Example cmdlet to use with Outlook Dutch client (calendar translates to agenda in dutch): Set-MailboxFolderPermission mailbox:\Agenda -User Default -AccessRights Reviewer
• The Set-MailboxCalendarFolder cmdlet configures publishing or sharing settings on a calendar folder of a specified mailbox. So, this cmdlet should be used when configuring Internet Calendar sharing.