Office 365 – Change default calendar to Reviewer


Client wanted to change every user’s calendar to review only.


  1. Connect-ExchangeOnline -UserPrincipalName
  2. $users = Get-Mailbox -Resultsize Unlimited
  3. foreach ($user in $users) { Write-Host -ForegroundColor green Setting permission for $($user.alias)… Set-MailboxFolderPermission -Identity $($user.alias):\calendar -User Default -AccessRights Reviewer }

Please note that this has to be run every time as it changes the current list of users rather than modify the default behaviour.