Managing Exchange Calendar invites during restore

When an Exchange calendar event is restored after being removed from attendees' calendars, it is recreated in the organizer's calendar, and an invitation is sent to the attendees.

To prevent calendar-related emails from being sent during the restore process, you can temporarily control mail flow using transport rules in the Exchange Admin Center (EAC). 

To control mail flow

1. In the Exchange Admin Center, navigate to Mail Flow > Rules.

Here, you’ll find various options to control mail flow for specific users or groups.

2. In your environment, create a custom rule.

The rule should target messages of calendar type and apply only to the relevant mailbox or distribution group.

Important: Be sure to adjust the conditions and actions according to your internal requirements.

Example:

3. Once configured, enable the rule before initiating the mailbox restore job.

This rule will suppress outgoing calendar-related messages during the restoration process.

4. After the restore is complete, disable the rule.

Restored calendar invites will remain intact in users’ mailboxes, and normal calendar message flow will resume.