Windows 11 · 25H2 · Release · Optional preview update

Preview Update for Windows 11 (26200.9550)

Windows 11 25H2: Current mainstream release

AI summary

This Windows 11 preview adds File Explorer refinements, Emoji 17.0, Copilot-key remapping, touchpad gestures, maximized-app accessibility, and saved-Wi-Fi recovery, alongside camera and File History fixes.

Generated from the package's release notes and forum coverage. Verify against Microsoft's release-health page before acting on it.

Microsoft's known issues — KB5124010

  • Issue Known issue After installing the September 8, 2026, Windows security update ( KB5124008 ), or later updates, some Credential Guard protected machine accounts might lose their secure channel with an on-premises Active Directory (AD) domain. Users might then be unable to sign in interactively with valid domain credentials and might receive a message stating that the trust relationship between the device and the domain failed. Offline sign-in using previously cached credentials might continue to work. AD replication and AD services on the domain controllers are not affected. This issue occurs because KB5124008 and later updates enable the Machine Identity Isolation feature. While the update does not direct Workaround: Important: This section contains information about modifying the registry. Before you modify the registry, back it up and make sure that you know how to restore it if a problem occurs. For more information, see How to back up and restore the registry in Windows . To work around this issue, disable Machine Identity Isolation using the same management method that was used to enable it. Choose the applicable option below: If Machine Identity Isolation was enabled by Intune policy, disable Machine Identity Isolation with Intune . If Machine Identity Isolation was enabled by Intune policy, disable Machine Identity Isolation with Intune . If Machine Identity Isolation was enabled by Group Policy,

Microsoft's release notes for KB5124010 ›

Known issues — reported on the forum

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