Applies To
Windows 11 version 23H2, all editions

Release Date:

9/23/2025

Version:

OS Build 22621.5984

Windows Secure Boot certificate expirationImportant: Secure Boot certificates used by most Windows devices are set to expire starting in June 2026. This might affect the ability of certain personal and business devices to boot securely if not updated in time. To avoid disruption, we recommend reviewing the guidance and taking action to update certificates in advance. For details and preparation steps, see Windows Secure Boot certificate expiration and CA updates.

To learn more about Windows update terminology, see types of Windows updates and monthly quality update types. To find an overview, see the update history page for Windows 11, version 23H2,  

Stay informed! Follow @WindowsUpdate for the latest updates from the Windows Release Health Dashboard.  ​​​​​​

​​​​End of servicing

Starting June 26, 2025, Windows 11 version 22H2 (Enterprise and Education editions) will no longer receive non-security preview updates. However, monthly security updates will continue through October 14, 2025. After that date, this version will reach the end of servicing and will no longer receive security updates. To stay protected and up to date, we recommend you upgrade to the latest version of Windows 11.

Learn more

Highlights

  • This non-security update includes quality improvements.

​​​​​​​Improvements​​​​​​​

Important: Use EKB KB5027397 to update to Windows 11, version 23H2.

This non-security update includes quality improvements. The following summary outlines key issues addressed by the KB after you install it. Also, included are available new features. The bold text within the brackets indicates the item or area of the change.

  • [Authentication] Fixed: An issue that caused Windows sign-in screen to stop responding after a user enters the SIM PIN during sign-in using a mobile broadband connection. 

  • [Browser] Fixed: This update addresses an issue that affects Microsoft Edge when running in Internet Explorer compatibility mode. It stops responding due to certain same-domain redirects.

  • [Country and Operator Settings Asset (COSA)] Fixed: This update brings profiles up to date for certain mobile operators. 

  • [Display Kernel] Fixed: This update addresses an issue that affects display configuration changes during Remote Desktop Protocol (RDP) sessions with multiple monitors. The system might shut down unexpectedly when disconnected from a docking station during a streaming session. 

  • [Input]   

    • Fixed: An issue where some characters didn’t display correctly when using the Chinese Input Method Editor (IME).  

    • Fixed:  This update addresses an issue where certain Chinese characters appeared as empty boxes in some text fields, such as those used in Connection Manager Administration Kit, when a character limit was set. 

  • [Networking (known issue)] Fixed: This update addresses an issue where you might not be able to connect to shared files and folders if you're using the Server Message Block (SMB) v1 protocol on NetBIOS over TCP/IP NetBIOS (NetBT). This can happen after installing update KB5065431.

  • [Printer] Fixed: An issue where viewing the printer queue in Settings for a shared printer caused the Print Queue user interface to stop working.

  • [System services and reliability] Fixed: Addresses an issue that caused McpManagement service to appear without a description on Windows. 

If you installed earlier updates, your device downloads and installs only the new updates contained in this package.

Windows 11 servicing stack update (KB5066412) - 22621.5983

This update makes quality improvements to the servicing stack, which is the component that installs Windows updates. Servicing stack updates (SSU) ensure that you have a robust and reliable servicing stack so that your devices can receive and install Microsoft updates. To learn more about SSUs, see Simplifying on-premises deployment of servicing stack updates.

Known issues in this update​​​​​​​

Microsoft is not currently aware of any issues with this udpate.

​​​​​​​​​​​​​​​​​​​​​​​​​​​​How to get this update

Before you install this update

Microsoft combines the latest servicing stack update (SSU) for your operating system with the latest cumulative update (LCU). For general information about SSUs, see Servicing stack updates and Servicing Stack Updates (SSU): Frequently Asked Questions.

Install this update

To install this update, use one of the following Windows and Microsoft release channels.

Available

Next Step

Included

Go to Settings > Update & Security > Windows Update. In the Optional updates available area, you'll find the link to download and install the update.

Check for optional updates

If you want to remove the LCU

To remove the LCU after installing the combined SSU and LCU package, use the DISM/Remove-Package command line option with the LCU package name as the argument. You can find the package name by using this command: DISM /online /get-packages.

Running Windows Update Standalone Installer (wusa.exe) with the /uninstall switch on the combined package will not work because the combined package contains the SSU. You cannot remove the SSU from the system after installation.

File information

For a list of the files provided in this update, download the file information for cumulative update 5065790.

For a list of the files provided in the servicing stack update, download the file information for the SSU (KB5066412) - versions 22621.5983. 

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