How to Force a Retention Policy to Apply Immediately in Microsoft 365 Exchange Online

How to Make a Retention Policy Apply Immediately in Microsoft 365 Exchange Online

When you create or assign a new retention policy in Exchange Online, it doesn’t take effect right away. Normally, Microsoft 365 relies on a background service called the Managed Folder Assistant (MFA), which automatically runs once every 7 days per mailbox. This can cause a delay before messages start moving to the archive or being processed according to your policy.

If you need the retention policy to start right away—especially for testing, compliance, or large rollouts—you can manually trigger the Managed Folder Assistant to run on specific mailboxes or across your entire tenant.

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Step 1: Connect to Exchange Online PowerShell

1. Open PowerShell on your computer.
2. Run the following commands to connect to Exchange Online: Install-Module ExchangeOnlineManagement Import-Module ExchangeOnlineManagement Connect-ExchangeOnline -UserPrincipalName admin@yourdomain.com Replace admin@yourdomain.com with your admin account. Once connected, you can run mailbox and retention-related commands directly.

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Step 2: Run the Managed Folder Assistant for a Single Mailbox

To apply the retention policy immediately to one mailbox, use:

Start-ManagedFolderAssistant -Identity user@yourdomain.com

• Replace user@yourdomain.com with the mailbox email.
• This command tells Exchange to immediately process that mailbox’s retention settings.
• Wait about 5–10 minutes for archiving or cleanup actions to start.

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Step 3: Verify if Archiving or Retention Started

You can check whether the policy has started working by doing one of the following:

Option 1: Using Outlook on the Web (OWA)

1. Sign in to Outlook Web Access.
2. Look for the In-Place Archive mailbox folder in the navigation pane.
3. If messages are moving automatically, the policy is active.

Option 2: Using the Exchange Admin Center (EAC)

1. Go to the Exchange Admin Center.
2. Navigate to Recipients > Mailboxes.
3. Select the user’s mailbox.
4. Under the Others tab, choose Manage mailbox archive.
5. You’ll see the archive mailbox size and last activity time.

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Step 4: Run the Managed Folder Assistant for All Mailboxes

To apply the retention policy across all user mailboxes in your organization, use:

Get-Mailbox -RecipientTypeDetails UserMailbox -ResultSize unlimited | ForEach {Start-ManagedFolderAssistant $_.Identity}

• This command loops through every mailbox and runs the Managed Folder Assistant.
• Execution may take time depending on the number and size of mailboxes.

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Step 5: Confirm That the Correct Retention Policy Is Assigned

If archiving still doesn’t begin, confirm the mailbox is linked to the right policy:

Get-Mailbox user@yourdomain.com | FL RetentionPolicy

You should see the assigned policy name.
If it’s wrong or blank, reassign it using:

Set-Mailbox user@yourdomain.com -RetentionPolicy "YourRetentionPolicyName"

Then re-run the Managed Folder Assistant command.

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Step 6: Monitor Progress

For larger mailboxes (30 GB+), it can take a few days for the retention process to complete. The Managed Folder Assistant works in the background and processes messages in batches.

To monitor archiving progress:

• Check the In-Place Archive mailbox size after a few hours or the next day.
• Use the Exchange Admin Center to view mailbox statistics.
• You can also check mailbox move reports using PowerShell: Get-MailboxStatistics -Identity user@yourdomain.com | FL DisplayName,TotalItemSize,LastLogonTime

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Additional Notes

• Service Load: Running the Managed Folder Assistant for all users at once can cause temporary system load. For large tenants, consider running it in smaller batches.
• Policy Evaluation: The MFA evaluates message timestamps, retention tags, and archive rules. If an item already meets the criteria, it will move or delete accordingly.
• Retention Tag Types: Remember, retention policies combine default, personal, and folder-based tags. Each tag can have different retention periods (e.g., 1 year, 5 years, Never Delete).
• Compliance Impact: Immediate application is especially useful for audits or regulatory cases where retention or deletion must begin right away.

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Summary

Running the Managed Folder Assistant manually lets you take full control of when retention policies apply in Exchange Online.
It’s a quick, safe, and Microsoft-supported way to enforce new policies instantly rather than waiting for the default 7-day processing cycle.

Key commands recap:

# Single mailbox
Start-ManagedFolderAssistant -Identity user@yourdomain.com

# All mailboxes
Get-Mailbox -RecipientTypeDetails UserMailbox -ResultSize unlimited | ForEach {Start-ManagedFolderAssistant $_.Identity}

# Verify assigned policy
Get-Mailbox user@yourdomain.com | FL RetentionPolicy