What is Litigation Hold?

Litigation Hold is a feature in Microsoft 365 Exchange that ensures the preservation of mailbox content for legal or compliance purposes. It prevents emails, calendar items, and other mailbox data from being permanently deleted or altered, even if users try to modify or remove them. This is particularly useful in situations where an organization needs to retain information for legal cases or investigations.

How to Enable Litigation Hold in Microsoft 365 Exchange

Litigation Hold in Microsoft 365 Exchange is a feature that preserves mailbox content to meet legal or compliance requirements. It ensures that emails and other mailbox items are retained even if a user deletes them. This guide walks you through enabling Litigation Hold step-by-step.

Step 1: Access the Exchange Admin Center (EAC)

1. Log in to the Microsoft 365 Admin Center at https://admin.microsoft.com.
2. In the left-hand navigation menu, under Admin Centers, select Exchange to open the Exchange Admin Center (EAC).

Step 2: Navigate to Mailbox Settings

1. In the EAC, go to Recipients > Mailboxes.
2. Locate the mailbox you want to place on Litigation Hold.
3. Click on the mailbox name to open its properties panel.

Step 3: Enable Litigation Hold

1. In the mailbox properties, select the Mailbox features tab.
2. Scroll down to the Litigation Hold section and click Enable.
3. Configure the following settings:
   • Hold duration (optional): Specify the number of days to retain the data. Leave it blank for an indefinite hold.
   • Notes (optional): Add a message or instructions for the user (e.g., explaining why the hold is applied).
4. Click Save to apply the Litigation Hold.

Step 4: Enable Litigation Hold Using PowerShell (Optional)

For admins who prefer PowerShell, follow these steps:

1. Open the Exchange Management Shell and connect to Exchange Online PowerShell:

   Connect-ExchangeOnline
   

2. Run the following command to enable Litigation Hold for a specific mailbox:

   Set-Mailbox -Identity "UserEmail@domain.com" -LitigationHoldEnabled $true -LitigationHoldDuration 365
   

   • Replace UserEmail@domain.com with the user’s email address.
   • Adjust the LitigationHoldDuration as needed (leave it out for indefinite hold).
3. Verify the Litigation Hold status:

   Get-Mailbox -Identity "UserEmail@domain.com" | Select-Object LitigationHoldEnabled, LitigationHoldDuration
   

Step 5: Verify Litigation Hold

To ensure the Litigation Hold is applied:

1. Go back to Recipients > Mailboxes in the EAC.
2. Select the mailbox and check the Mailbox features tab to confirm the hold is enabled.
3. Alternatively, use PowerShell to verify the status (see Step 4).

Step 6: Search and Export Data (eDiscovery)

1. Navigate to the Microsoft Purview Compliance Portal: https://compliance.microsoft.com.
2. Go to Content Search under the eDiscovery section.
3. Create a new search query targeting the user’s mailbox.
4. Export the results for legal or compliance review.

Best Practices and Notes

• Storage Limits: Mailboxes under Litigation Hold have a default storage limit of 100 GB. Enable the auto-expanding archive feature if additional storage is needed.
• Notification: Inform the user that their mailbox is on hold and explain what it means (if applicable).
• Auditing: All actions related to Litigation Hold are logged for compliance.
• Release of Hold: After the legal case or investigation is resolved, remove the hold to resume normal retention policies.

By following this guide, you can successfully enable Litigation Hold in Microsoft 365 Exchange to ensure compliance with legal and regulatory requirements.