You want to know when DLP Endpoint Agents will support the "new Outlook"

Products

• Data Loss Prevention Core Package
• Data Loss Prevention Enterprise Suite
• Data Loss Prevention Endpoint Suite
• Data Loss Prevention Endpoint Prevent
• Data Loss Prevention Endpoint Discover
• Data Loss Prevention

Issue/Introduction

You've heard about the latest version of Outlook and want to know when DLP Endpoint Agents will support the "new Outlook".

Environment

All DLP versions below 16.1

Endpoint Agents for Windows and macOS

Cause

Microsoft has released updated versions of Outlook with new functionality that requires 3rd party vendors to use a new on-send Web add-in for monitoring or modifying message content.

Outlook add-ins overview - Office Add-ins | Microsoft Learn

"Outlook add-ins are different from COM or VSTO add-ins, which are older integrations specific to Outlook running on Windows. Unlike COM add-ins, Outlook add-ins don't have any code physically installed on the user's device or Outlook client. For an Outlook add-in, Outlook reads the manifest and hooks up the specified controls in the UI, and then loads the JavaScript and HTML. The web components all run in the context of a browser or webview control in a sandbox."

Additionally:

"COM and VSTO add-ins aren't supported in the new Outlook on Windows that's currently in preview."

Resolution

DLP version 16.1 provides Full Support for Monitoring the New Outlook, refer to configuration: Monitoring Microsoft Outlook Emails Using the Web Add-in on Windows and macOS Endpoints

For all other DLP versions Mac Agents, DLP support for the new Outlook model has been available for the macOS since DLP 15.8.

For Windows Agents, the release requires a new on-send web add-in for Outlook, available in the Release Update of DLP (16.0 RU2). This feature will enable the DLP Agent to monitor user actions in the New Outlook view in Microsoft Outlook as well as in Outlook Web Access on Windows endpoints. 

For the coming Windows release of this feature:

• As the New Outlook view is currently a Microsoft preview product, Symantec cannot ensure a similar level of functionality as the previously used COM plug-in. Therefore, Symantec is releasing the add-in as a DLP preview feature for testing purposes only, and strongly recommends that you avoid deploying it in a production environment.
• The on-send web add-in monitors Microsoft 365 accounts and does not monitor other types of mailboxes.
• Symantec DLP will continue to support the COM plug-in for monitoring Outlook in the classic view.

Additional Information

For those who wish to prevent users from enabling the new Outlook until monitoring is available, see the steps given in the following Advisory:

The new Microsoft Outlook prevents DLP from monitoring emails on Windows endpoints

As well as the Microsoft instructions for doing the same:

Enable or disable access to the new Outlook for Windows | Microsoft Learn

 

For more information about the development of the new Outlook:

The new Outlook for Mac - Microsoft Support

Develop Outlook add-ins for the new Outlook on Windows (preview) - Office Add-ins | Microsoft Learn