Microsoft Outlook: Customizable oversharing dialog for DLP in New Outlook

[Introduction]

New Outlook for Windows will now support the ability to show a customizable oversharing dialog for Data Loss Prevention (DLP). This enhancement allows organizations to tailor the experience for end users when oversharing is detected, improving clarity and compliance.

This message is associated with Microsoft 365 Roadmap ID 498921.

[When this will happen]

General Availability (Worldwide): Rollout begins in early January 2026 and is expected to complete by late January 2026.

General Availability (GCC): Rollout begins in early February 2026 and is expected to complete by late February 2026.

[How this affects your organization]

• Who is affected: Admins managing DLP policies in New Outlook for Windows.
• What will happen:
  • New Outlook will display a customizable oversharing dialog when DLP rules are triggered.
  • Customization options include:
    • Custom titles and body text with multi-language support (up to 10 languages).
    • Business justification options (up to 3 predefined + 1 optional free-text).
    • Dynamic tokens for matched recipients, sensitivity labels, and attachment filenames.
    • Text formatting (Bold, Italic, Underline, Line breaks).
  • If this feature is already enabled in classic Outlook, it will work in New Outlook without additional action.
  • Feature is OFF by default unless configured by admins.

[What you can do to prepare]

• No action is required unless you want to enable this feature.
• If enabling, configure settings in the Compliance portal under DLP policy tips.

Learn more: Data loss prevention policy tip reference for Outlook for Microsoft 365 | Microsoft Purview | Microsoft Learn

[Compliance considerations]

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