May 12, 2026—KB5087538 (OS Build 17763.8755)

Ισχύει για
Windows Server 2019 Win 10 Ent LTSC 2019

Note

  • Windows Secure Boot certificate expiration
  • Important: Secure Boot certificates used by most Windows devices are set to expire starting in June 2026. Microsoft has been updating these certificates on consumer and non-managed business devices for the past months. Devices that haven’t received the newer certificates will continue to start and operate normally, and standard Windows updates will continue to install. We will continue to install the newer certificates via Windows updates in the coming months.
  • You can check your PC status on the Windows Security app. If you are an IT administrator, follow the guidance on the Secure Boot Playbook for Windows clients and Windows Server.

Summary

This article lists the security issues and quality improvements included in this cumulative security update.

Applies to: Windows Server 2019

This security update includes fixes and quality improvements that are part of the following update:

The following is a summary of the issues that this update addresses when you install this update. The bold text within the brackets indicates the item or area of the change we are documenting.

  • [Remote Desktop security warnings (known issue)] Fixed: The Remote Desktop Connection security warning dialog might render incorrectly in multi-monitor configurations with different display scaling settings. This issue might occur after installing the Windows security update released on or after April 14, 2026 (such as KB5082123).

  • [Secure Boot]

    • This update enables dynamic status reporting for Secure Boot states in Windows Security App.
    • With this update, Windows quality updates include additional high confidence device targeting data, increasing coverage of devices eligible to automatically receive new Secure Boot certificates. Devices receive the new certificates only after demonstrating sufficient successful update signals, maintaining a controlled and phased rollout.
    • This update adds a new SecureBoot folder under C:\Windows on eligible devices. The folder contains example scripts intended for organizations with IT professionals who actively manage updates across their device fleet. These scripts can be used to detect Secure Boot certificate update status and automate deployment via a safe rollout mechanism in an Active Directory environment. For more information, see Sample Secure Boot E2E Automation Guide.

  • [Sign-In] Fixed: After you install the Windows update released on or after March 10, 2026, some users might experience an issue signing in to apps with a Microsoft account. Even when the device has a working Internet connection, a “no Internet” error appears during sign in and prevents access to Microsoft services and apps such as Microsoft Teams.

  • [Daylight Savings Time] Update for Arab Republic of Egypt to support the government DST change order in 2023.

If you installed earlier updates, only the new updates contained in this package will be downloaded and installed on your device.

For more information about security vulnerabilities, please refer to the new Security Update Guide website and the May 2026 Security Updates.

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 1809, see its update history page.

Known issues in this update

We are currently not aware of any issues with this update.

Servicing stack update (KB5089760) - 17763.8754

Microsoft now combines the latest servicing stack update (SSU) for your operating system with the latest cumulative update (LCU). SSUs improves the reliability of the update process and includes fixes to the servicing stack, the component that installs Windows updates.

Note: This servicing stack update (SSU) includes enhanced logic to verify whether a device is hosted on Azure, leveraging an updated certificate chain for validation. To ensure that the device can access the required certificate update domains to successfully download and install certificate updates, see Certificate downloads and revocation lists and Azure Certificate Authority details. To learn more about SSUs, see Servicing stack updates.

How to get this update

Before you install this update

You must have installed the August 10, 2021 SSU (KB5005112) before installing this cumulative update.

Get and install this update

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

Available Next Step
Available This update will be downloaded and installed automatically from Windows Update.

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.

Note: The English (United States) version of this software update might contain files for additional languages.

Download Icon Download the file information for this cumulative update KB5087538 now.

Download Icon Download the file information for the SSU (KB5089760) - version 17763.8754 update now.

If you want to remove this update

Note

Notice for Microsoft Store application updates

Note

Windows updates do not install Microsoft Store application updates. If you are an enterprise user, see Microsoft Store apps - Configuration Manager. If you are a consumer user, see Get updates for apps and games in Microsoft Store.

End of support information

Note

Change log

Change date Change description
May 13, 2026
  • Added the following release note for Secure Boot:

    This update adds a new SecureBoot folder under C:\Windows on eligible devices. The folder contains example scripts intended for organizations with IT professionals who actively manage updates across their device fleet. These scripts can be used to detect Secure Boot certificate update status and automate deployment via a safe rollout mechanism in an Active Directory environment. For more information, see Sample Secure Boot E2E Automation Guide.