Wipe Microsoft 365 Mailbox After License Removal Print

Overview

To fully wipe a Microsoft 365 mailbox without deleting the user account, you must:

• Remove the Exchange Online license
• Permanently clear the mailbox using PowerShell
• Reassign the license to provision a new, empty mailbox

Prerequisites

• Microsoft 365 Administrator access
• Ability to connect to Exchange Online PowerShell

Step 1 - Remove Exchange Online License

1. Go to the Microsoft 365 Admin Center
2. Navigate to Users > Active users
3. Select the user
4. Open the Licenses and Apps tab
5. Uncheck:
   • Exchange Online Plan 1 or Plan 2
   • Any other Exchange related licenses
6. Click Save

This will soft-delete the mailbox. It remains recoverable for approximately 30 days unless permanently cleared.

Step 2 - Connect to Exchange Online PowerShell

Open PowerShell as Administrator and run:

Connect-ExchangeOnline

Step 3 - Permanently Clear Mailbox Data

Run the following command:

Set-User -Identity "<UserPrincipalName>" -PermanentlyClearPreviousMailboxInfo

• Type Y and press Enter when prompted

This immediately and permanently deletes the mailbox data while leaving the user account intact.

Step 4 - Verify Mailbox Removal (Optional)

Run:

Get-User <Identity> | fl *Workload*

Confirm mailbox-related attributes are empty or null.

Step 5 - Reassign Exchange Online License

1. Return to Microsoft 365 Admin Center
2. Go to Users > Active users
3. Select the user
4. Open Licenses and Apps
5. Re-enable Exchange Online Plan
6. Click Save

A brand new, empty mailbox will be created for the user.

Notes

• The mailbox removal may take a few minutes to fully process
• The user account and other services like OneDrive and Teams are not affected
• This is the recommended method when a full mailbox reset is required without deleting the user