September 25, 2025—KB5066198 (OS Build 19045.6396) Preview
Applies To
Release Date:
25/09/2025
Version:
OS Build 19045.6396
Windows Secure Boot certificate expirationÂ
Important: 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.
Support for Windows 10 will end in October 2025
After October 14, 2025, Microsoft will no longer provide free software updates from Windows Update, technical assistance, or security fixes for Windows 10. Your PC will still work, but we recommend moving to Windows 11.
Summary
​​​​​​​Windows 10, version 22H2
Important:Â Use EKB KB5015684 to update to Windows 10, version 22H2.
This preview update contains the fixes and quality improvements contained in the following update:
The following is a summary of the key issues that this update addresses. The bold text within the brackets indicates the item or area of the change we are documenting.
-
[SMBv1 protocol connectivity (known issue)] Fixed: 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 KB5065429.
-
[Autopilot Enrollment Status Page (ESP) (known issue)] Fixed: An issue when using Windows Autopilot to deploy Windows 10, version 22H2 to devices with the Enrollment Status Page (ESP) configured might find that the ESP doesn't load during the Out-of-Box Experience (OOBE).
If you installed earlier updates, only the new updates contained in this package will be downloaded and installed on your device.
For information about Windows update terminology, see the article about the types of Windows updates and the monthly quality update types. For an overview of Windows 10, version 22H2, see its update history page.
Note Follow @WindowsUpdate to find out when new content is published to the Windows release health dashboard.
Servicing stack update (KB5066411) - 19045.6389
Microsoft now combines the latest servicing stack update (SSU) for your operating system with the latest cumulative update (LCU). SSUs improve the reliability of the update process to mitigate potential issues while installing updates.
This update makes quality improvements to the servicing stack, which is the component that installs Windows updates. To learn more about SSUs, see Servicing stack updates and Servicing Stack Updates (SSU): Frequently Asked Questions.
Known issues in this update​​​​​​​
We are not currently aware of any issues with this update.
How to get this update
Before you install this update
Based on your installation scenario, choose one of the following:
-
For offline OS image servicing:
If your image does not have the July 25, 2023 (KB5028244) or later LCU, you must install the special standalone October 13, 2023 SSU (KB5031539) before installing this update.
-
For Windows Server Update Services (WSUS) deployment or when installing the standalone package from Microsoft Update Catalog:
If your devices do not have the May 11, 2021 (KB5003173) or later LCU, you must install the special standalone August 10, 2021 SSU (KB5005260) before installing this update.
Install this update
To install this update, use one of the following Windows and Microsoft release channels.
|
Available |
Next Step |
|
|
Go to Settings > Update & Security > Windows Update. In the Optional updates available area, you will find the link to download and install the update. |
|
Available |
Next Step |
|
|
These changes will be included in the next security update to Windows Update for Business. |
|
Available |
Next Step |
|
|
To get the standalone package for this update, go to the Microsoft Update Catalog website. For information about how to download and install updates from the Update Catalog, see How to download updates that include drivers and hotfixes from the Windows Update Catalog. |
|
Available |
Next Step |
|
|
You can import this update into Windows Server Update Services (WSUS) manually. See the Microsoft Update Catalog for instructions. |
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
A list of the files that are included in this update are provided in a CSV (Comma delimited) (*.csv) file. The file can be opened in a text editor such as Notepad or in Microsoft Excel.
Need more help?
Want more options?
Explore subscription benefits, browse training courses, learn how to secure your device, and more.
Communities help you ask and answer questions, give feedback, and hear from experts with rich knowledge.
