Microsoft Defender XDR: Enhancing email remediation with Sender’s copy clean-up features

Updated August 15, 2024: We have updated the rollout timeline below. Thank you for your patience..

Coming soon to Microsoft Defender XDR: We will enhance email remediation capabilities with new Sender's copy clean-up features in Threat Explorer, email entity, Summary Panel, and Advanced hunting. These new features will streamline the process of managing Sent items, particularly for admins who use Soft delete and Move to inbox actions.

Key Features

• Integration with Soft delete: Sender's copy clean-up will be incorporated as part of the Soft delete action.
• Wide support: This action will be supported across various Defender XDR platforms including Threat Explorer, Take Action wizard from the email entity, Summary Panel, Advanced hunting, and through Microsoft Graph API.
• Undo capability: An undo action will be available, allowing you to reverse the clean-up by moving items back to the Sent folder.

Note: Sender's copy clean-up will apply to intra-organization emails and outbound emails, ensuring that only the sender's copy is soft deleted for these emails and inbound messages are out of scope.

When this will happen

General Availability (Worldwide): We will begin rolling out end of May 2024 and expect to complete by early September 2024 (previously late July).

How this will affect your organization

Before this rollout, admins did not have a way to remove harmful emails from a sender's Sent items.

After rollout: This step-by-step scenario explains the functionality of Sender's copy clean-up:

You as the admin have already investigated in Threat Explorer, email entity, or Advanced hunting and have selected entities to remediate.

1. Create remediation: After your entity selection, you choose an action and create the remediation. For the Soft delete action, these items will be visible in the Take action wizard:

• Checkbox for Sender's copy. Select this option to clean the messages from sender's Sent folder.
• Email count: Displays the number of emails submitted. This count will reflect sender’s copy as well.
• Sender’s entities in a separate tab.

2. As the remediation begins, the approval ID to track the action is displayed (Note: This is the same as before the rollout.)

3. Track the remediation status: The Unified Action Center (Actions & submissions > Action center > History) contains all the approved actions. You can open any manual remediation action entry in Action center to:

• View the email count: This count will be same as submitted email count.
• Review the action logs: The email count and action logs will reflect the status of remediable, non-remediable, failed, and timed-out emails, including the sender's copy.
• Export action logs: The export feature will include the new column IsSendersCopy to capture the sender entities and corresponding action status.

4. Undo sent items. The undo capability ensures that you have greater control and flexibility when managing email remediation, providing a safety net for actions taken in error or needing revision. Select the checkbox for Move to Inbox to trigger undo for the recipient copy and previously deleted sender’s copy of a message.

From Advanced hunting: The Delete sender's copy option under Delete email > Soft delete:

From Threat Explorer: The Delete sender's copy option under Move to mailbox folder > Soft delete:

From Threat Explorer: The Undo sender's copy option under Move to mailbox folder > Inbox:

What you need to do to prepare

This rollout will happen automatically by the specified date with no admin action required before the rollout. You may want to notify your admins about this change and update any relevant documentation as appropriate.

Learn more:

• Threat hunting in Threat Explorer and Real-time detections - Microsoft Defender for Office 365 | Microsoft Learn
• Threat Explorer- Threat hunting in Threat Explorer and Real-time detections - Microsoft Defender for Office 365 | Microsoft Learn
• Remediation- Remediate malicious email that was delivered in Office 365 - Microsoft Defender for Office 365 | Microsoft Learn
• Advanced hunting-Take action on advanced hunting query results in Microsoft Defender XDR - Microsoft Defender XDR | Microsoft Learn
• MDO What's new- What's new in Microsoft Defender for Office 365 - Microsoft Defender for Office 365 | Microsoft Learn
• XDR what's new - What's new in Microsoft Defender XDR - Microsoft Defender XDR | Microsoft Learn