In my organization, we are using Outlook within an Office 365 tenant. Users often share calendars with each other, including both primary (default) and secondary calendars. When a calendar is shared, a notification email is typically sent to the recipient. This email includes an “Add this calendar” button, allowing the recipient to easily add the shared calendar to their Outlook.

However, there are cases where calendar permissions are assigned using PowerShell cmdlets (e.g., Add-MailboxFolderPermission) without triggering the notification email to the recipient. In such scenarios, users do not receive the “Add this calendar” email, and thus, they don’t have an easy way to add the shared calendar to their Outlook.

If a calendar has been shared with me in my Office 365 tenant but I did not receive the notification email (or I have deleted it), how can I manually add that shared calendar to my Outlook or Outlook Web Access (OWA)? Are there any alternative methods or PowerShell commands that can help me retrieve and add the shared calendar without relying on the email notification?