SharePoint Sensitivity Labels: OneNote and MP4 Now Supported

An expanding protection scope

SharePoint Online has just taken a quiet but significant step: OneNote and MP4 files now officially join the list of formats fully supported by sensitivity labels. No official announcement, no message in the admin center — the news appeared in Microsoft documentation without fanfare, though hints had been dropped at events like Ignite 2025.

This extension continues the momentum from last year's addition of support for user-defined permissions labels in SharePoint Online. It now enables the platform to encrypt and decrypt these formats for accessibility to Microsoft Purview solutions: Microsoft Search indexing, eDiscovery, and Data Loss Prevention (DLP).

Enabling sensitivity label support in SharePoint Online

Before configuring anything for OneNote or MP4, global label support must be enabled at the tenant level. This is done via the SharePoint Online management module with the following command:

1Set-SPOTenant -EnableAIPIntegration $true

Once enabled, SharePoint Online and OneDrive for Business can encrypt and decrypt the content of labeled files while maintaining proper functioning of associated Purview services.

Enabling support by file type

Global enablement is not sufficient: PDF, OneNote, and MP4 must each be enabled separately. By default, SharePoint Online can store these formats but cannot process their content.

PDF Files

1Set-SPOTenant -EnableSensitivityLabelforPDF $true

Once enabled, SharePoint Online and OneDrive for Business support PDFs labeled by Adobe Acrobat (subscription), PDFs exported from Word, Excel or PowerPoint, and PDFs labeled outside Microsoft 365 via the Microsoft Information Protection (MIP) extension for Windows Explorer.

OneNote Files

1Set-SPOTenant -EnableSensitivityLabelforOneNote $true

OneNote support has an important characteristic: labels are applied at the section level, not to the entire notebook. Each section can thus have a different label. This granularity is valuable in educational or research contexts, where notebooks often contain highly confidential information.

MP4 Files (Video)

1Set-SPOTenant -EnableSensitivityLabelforVideoFiles $true

Several constraints apply specifically to MP4 files:

• Automatic label application is not supported.
• Labels with user-defined permissions are not compatible.
• When a label with encryption is applied, users can no longer download the file from SharePoint Online.
• Online playback remains possible via viewers built into SharePoint Online, Teams, and Clipchamp.

Teams meeting recordings (audio only or audio and video), stored as MP4 files in the meeting organizer's OneDrive for Business account, can inherit sensitivity labels defined in meeting settings. In fact, the documentation on protecting Teams meeting recordings was the first to reveal MP4 support.

Licensing impact: what you need to plan for

Enabling the settings does not automatically label existing files. Two approaches are available for labeling content:

The Microsoft Purview Information Protection client for files outside Microsoft 365

For files stored outside Microsoft 365, the Microsoft Purview Information Protection client (successor to the Azure Information Protection client) allows labels to be applied directly from Windows Explorer. It supports many formats: JPEG, PDF, MP3, MP4, and many others.

When this client applies a label with encryption, the behavior varies by file type:

• Office and PDF files: the label is embedded in the file's metadata, just as SharePoint Online would do.
• Other formats: the client generates a Rights Management-protected file, which can only be opened by a compatible viewer — the one built into the Windows client or a dedicated application.

A file protected this way can be uploaded to SharePoint Online or OneDrive for Business, but its content remains inaccessible to Purview solutions — the service cannot decrypt it.

MacOS: File Labeler and File Viewer coming soon

According to message center notification MC1326509 (May 29, 2026), Microsoft plans to launch two MacOS applications — File Labeler and File Viewer — to apply labels to MacOS files and view the content of protected files. Their availability is announced as "on or around September 30, 2026".

What this extended support changes for your Purview governance

With the addition of OneNote and MP4, SharePoint Online now covers a very large portion of common business content. Practical consequences for administrators:

• Teams recordings can be governed through the same DLP and eDiscovery policies as your Office documents.
• OneNote notebooks used in sensitive contexts (HR, R&D, training) finally enter the scope of Purview compliance.
• The reference documentation for configuring these settings is available on Microsoft Learn.

Key takeaways

• First enable Set-SPOTenant -EnableAIPIntegration $true, then each format separately.
• MP4: online playback maintained, download blocked if encrypted label, no automatic labeling.
• OneNote: granularity at section level, not notebook level, inaccessible from SharePoint web interface.
• No existing files are automatically labeled after enablement.
• MacOS File Labeler and File Viewer applications are expected late September 2026.