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What's new in the Windows 11 Insider builds for 8 September 2026

Affects
  • Windows 11, version 26H2
  • Build 26340.9212
  • Build 26340.9233
Maya Reyes4 min read

Quick answer

The September 2026 Windows 11 Insider updates for the Experimental channel bring Build 26340.9212 and Build 26340.9233. Key highlights include individual desktop app privacy controls, a modernized WinUI AutoPlay dialog, automatic Wi-Fi profile reuse in WinRE, and a redesigned File Explorer context menu.

Microsoft has released experimental updates for Windows 11 Insiders, focusing on core interface refinements, granular privacy management, accessibility options, and system reliability fixes. These updates apply to devices enrolled in the Experimental channel running Windows 11, version 26H2 via an enablement package, specifically encompassing Build 26340.9212 and Build 26340.9233.

These builds affect registered Windows Insiders who test early platform features and experimental concepts. Because these releases are part of Microsoft's active development pipeline, they offer an early look at features that may eventually ship in future general availability updates. The updates bring notable changes across File Explorer, Settings, system dialogs, lock screen widgets, and recovery networking.

Highlights

  • Redesigned File Explorer context menu: Introduced an updated right-click context menu in File Explorer structured to reduce top-level visual clutter, keep high-frequency actions easily accessible, and add a dedicated Settings configuration page for menu customization.
  • File Explorer file previews: Enabled automatic file previewing in the preview pane for downloaded PDF and non-HTML web files, and resolved an issue that caused image previews to display an unexpected thick band across the middle.
  • Granular desktop app privacy permissions: Added individual control over camera, microphone, and location permissions for desktop applications under Settings > Privacy & security, replacing the previous single device-wide toggle.
  • Modernized AutoPlay dialog: Rebuilt the AutoPlay experience with WinUI to support dark mode, align with Windows 11 visual design, adjust dynamically to text scaling settings, and dock notifications inside the notification center.
  • New accessibility window setting: Introduced an "Open apps maximized" setting under Settings > Accessibility > Visual effects that automatically forces application windows to open in a maximized state.
  • WinRE Wi-Fi credential sharing: Upgraded the Windows Recovery Environment (WinRE) to automatically reuse eligible saved Wi-Fi profiles—including certificate-based networks—from the main Windows OS when network connectivity is required during recovery operations.
  • Streamlined lock screen widgets: Updated lock screen widgets so that Weather serves as the primary widget, reducing recommended clutter and allowing users to customize visible widgets under Settings > Personalization > Lock screen.
  • Emoji 17.0 support: Added new emoji including distorted face, fight cloud, and hairy creature (accessible via Windows key plus Period), while updating design details on saluting face, face with peeking eye, goose, lotus, and kissing cat.
  • Magnifier visual refresh: Modernized the Magnifier toolbar with updated icons aligned with Windows 11 visual design alongside refined spacing and padding, while keeping underlying functionality unchanged.
  • Get Started app expansion: Updated the Get Started experience with new pages for app installation, website pinning, and personalized desktop themes.
  • Personalization and background fixes: Added support for DIB image files as desktop backgrounds, allowed slideshow wallpapers across multiple desktops without reverting to Picture mode, and improved background image preview resolution.
  • Input and system fixes: Resolved bugs causing mouse cursor invisibility in specific apps, taskbar animation freezes, third-party IME status window alignment issues, and Settings app crashes on the Date & Time page.

Known issues

Microsoft reports no known issues for this update.

Should you install it?

These experimental builds are intended primarily for tech enthusiasts, early adopters, and Windows Insiders who want to evaluate upcoming features ahead of public release. If you enjoy testing new capabilities like individualized app privacy toggles, updated WinUI dialogs, and automated WinRE network connectivity, installing these preview updates provides early access to Microsoft's latest development work.

However, because these releases originate from the Experimental channel and represent pre-release software delivered via enablement packages on Windows 11, version 26H2, they may contain variable system stability or unlocalized elements. These updates are completely optional previews rather than mandatory security updates. Users who require a guaranteed stable environment for daily work should remain on standard retail releases or switch to the Release Preview channel.

How to get it

To receive these preview builds, your device must be enrolled in the Windows Insider Program under the Experimental channel.

  1. Open the Settings app on your Windows 11 device.
  2. Select Windows Update from the sidebar menu.
  3. Click on Windows Insider Program and verify that your device is enrolled in the Experimental channel.
  4. Return to the main Windows Update screen and select Check for updates.
  5. Once Build 26340.9212 or Build 26340.9233 is detected, allow Windows Update to download and install the update package.
  6. Restart your device when prompted to complete the installation.

Note that preview builds for the Experimental channel are distributed directly through Windows Update to enrolled devices. They are not made available as standalone offline installers on the public Microsoft Update Catalog website. If you encounter issues receiving preview updates, check your Insider channel settings or review feature flags under Settings > Windows Update > Windows Insider Program > Flags.

Sources

Frequently asked questions

What build numbers are included in the September 2026 Windows 11 Insider updates?

The preview updates for the Experimental channel include Build 26340.9212 and Build 26340.9233, based on Windows 11, version 26H2.

How do I manage camera and microphone permissions for individual desktop apps?

Navigate to Settings > Privacy & security > Camera, Microphone, or Location to review and manage access permissions for individual desktop applications.

Can I download these Windows 11 Insider builds from the Microsoft Update Catalog?

No, preview builds for the Experimental channel are distributed directly through Windows Update to enrolled devices rather than the public Microsoft Update Catalog.

What changes were made to lock screen widgets in these builds?

Weather is now set as the primary lock screen widget to reduce visual clutter, and users can customize visible widgets under Settings > Personalization > Lock screen.

Checked against Microsoft's release notes on ; re-checked when a new build ships.

Written by

Maya Reyes

Covers Windows 11 update releases and the problems that follow them. Tracks Microsoft's release-health notes daily and flags known issues the same day they appear.

More from Maya Reyes

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