MC1198702: Microsoft Outlook: Wait on Send for Data loss Prevention

New Outlook for Windows will support Wait on Send for Data Loss Prevention, blocking email sending until DLP evaluation completes or timeout occurs. This feature is disabled by default and controlled via Exchange mailbox settings, allowing users to multitask during evaluation with configurable ov...

[Introduction]

New Outlook for Windows will support Wait on Send for Oversharing, allowing admins to block email sending if Data Loss Prevention (DLP) policy evaluation is not completed for labeled or sensitive content. The new experience allows for multi-tasking and does not block the user from using New Outlook even when mail is in evaluation.

The wait-on-send experience is controlled through Exchange mailbox parameters:

  • DLPWaitOnSendEnabled – Boolean (true or false), Default: false
  • DLPWaitOnSendTimeout – Integer (0–10000 seconds), Default: 9999

Specifies how long Outlook waits for the DLP evaluation to finish before offering an override.

Example: If the value is set to 25 seconds, Outlook will wait up to 25 seconds for the evaluation to complete before allowing the user to override and send the email without waiting for the evaluation to finish.

Note: This does not stop the evaluation after the set time. It simply allows the user to override while the evaluation continues. If the user prefers, they can wait until the evaluation is fully completed.

- When DLPWaitOnSendTimeout = 0, user will immediately see “Send Anyway” in the info bar of mail. 

- When DLPWaitOnSendTimeout >= 9999, user will never be allowed to send the email without DLP evaluation getting completed. 

    This message is associated with Microsoft 365 Roadmap ID 498920.

    [When this will happen]

    • General Availability (Worldwide): Early January 2026 – Late January 2026
    • General Availability (GCC): Early January 2026 – Early March 2026

    [How this affects your organization]

    • Who is affected: Admins managing New Outlook for Windows users.
    • What will happen:
      • New Outlook will support Wait on Send for DLP evaluation.
      • Feature is disabled by default; admins must enable it via Exchange mailbox settings.
      • Users can continue working while mail is under evaluation.
      • Override behavior depends on DLPWaitOnSendTimeout configuration.

    [What you can do to prepare]

    Learn more: Wait on Send dialog support for Oversharing for Outlook for Microsoft 365 | Microsoft Learn

      [Compliance considerations]

      No compliance considerations identified. Review as appropriate for your organization.