Microsoft has rolled out the KB5070311 preview cumulative update for Windows 11, bringing 49 changes, including fixes for File Explorer freezes and search problems.
KB5070311 is an additional preview update that is delivered at the end of each month, allowing IT administrators to test Windows bug fixes, upgrades, and new features that will be available in next month’s Patch Tuesday release.
Unlike the Patch Tuesday cumulative updates, monthly non-security preview releases solely contain quality enhancements and do not include security fixes.
Microsoft resolved a reported issue that occurred after installing the most recent updates, causing the explorer.exe process and the taskbar to cease responding after certain notifications, with the November optional update KB5070311.
It also addresses File Explorer search issues on certain SMB shares and an LSASS instability caused by an access violation.
To install KB5070311, go to Settings, select Windows Update, and then click ‘Check for Updates.’ Because this is an optional update, you will be invited to install it by clicking the ‘Download and Install’ button. After obtaining the preview update from the Microsoft Update Catalogue, you can manually install it.
After installation, this optional non-security preview update will upgrade Windows 11 25H2 and 24H2 devices to builds 26200.7309 and 26100.7309, respectively.
The preview version for November 2025 includes further fixes and enhancements, some of which are highlighted below.
The search results menu shows more results, making it easier to find and change your settings. Users can check through all search results by using a scroll bar.
The Windows Studio Effects, which offers AI-powered camera upgrades, can be used with an external camera, such as a USB webcam or your laptop’s built-in back camera (Copilot + PCs).
When you choose Windows Spotlight as your desktop background, the context menu now contains two options: To discover more about this backdrop and the Next desktop background.
File Explorer now provides a more uniform dark mode experience.
In a separate message centre update, Microsoft stated that it will not provide a preview update in December, but will resume the usual roll-out schedule in January.
The company noted this because of minimal operations during the Western holidays and the upcoming new year, there will be no December 2025 non-security preview update.
“A monthly security update will be provided for December 2025. Regular monthly servicing for both security and non-security preview updates will resume in January 2026.”
Furthermore Microsoft stated that it is continuing working to resolve a known issue identified last week that causes the password sign-in option to disappear from the lock screen settings.
The standalone installer (.msu file) is available for enterprise environments or manual installation via the Microsoft Update Catalogue.
For known Issues which is as a result of the installation of this update, some users have complained that File Explorer may briefly flash white screens when using dark mode. Microsoft is aware of the problem and is working on a solution.