April 14, 2026—KB5082198 (OS Build 14393.9060)

Applies to: Windows Server 2016

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

• March 10, 2026—KB5078938 (OS Build 14393.8957)

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

• [Windows Configuration System (WinCS)] This update addresses an issue that affects Windows Configuration System (WinCS) on Windows 10, version 1607 and Windows Server 2016. Some WinCS components were missing. Because of this, you could not turn on Secure Boot using WinCS.

• [Remote Desktop] This update improves protection against phishing attacks that use Remote Desktop (.rdp) files. When you open an .rdp file, Remote Desktop shows all requested connection settings before it connects, with each setting turned off by default. A one-time security warning also appears the first time you open an .rdp file on a device. For more information, see Understanding security warnings when opening Remote Desktop (RDP) files.

• [Windows Deployment Services (WDS)] This update disables the “Hands-Free Deployment” feature in WDS by default and is no longer a supported feature. For more information about this change, see Windows Deployment Services (WDS) Hands-Free Deployment Hardening Guidance related to CVE-2026-0386.

• [Kerberos protocol] This update changes the default DefaultDomainSupportedEncTypes value for Kerberos Key Distribution Center (KDC) operations to leverage AES-SHA1 for accounts that do not have an explicit msds-SupportedEncryptionTypes Active Directory attribute defined. For more information see, How to manage Kerberos KDC usage of RC4 for service account ticket issuance changes related to CVE-2026-20833.

• [Secure Boot] 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. ​​​​​​​

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 April 2026 Security Updates.

For more information about Windows 10, version 1607, see its update history page.

For information about Windows update terminology, see the article about the types of Windows updates and the monthly quality update types.

Known issues in this update

Domain controllers might restart repeatedly after installing this update

Symptoms	Resolution
After installing this update, domain controllers in environments with multiple domains in the forest that use Privileged Access Management (PAM), might experience LSASS crashes during startup. As a result, affected DCs might restart repeatedly, preventing authentication and directory services from functioning, and potentially rendering the domain unavailable.	This issue is addressed in out-of-band update KB5091572.​​​​​​​

Warnings related to Remote Desktop might not display correctly

Symptoms	Workaround	Notes
After installing this update, the security warning that appears when opening Remote Desktop (RDP) files might not display correctly in some cases. This issue might occur when you use more than one monitor with different display scaling settings (for example, one display set to 100% and another set to 125%). When this happens, the warning window might show overlapping text or partially hidden buttons, which can make the message difficult to read or interact with.	To help the warning window display correctly, set the same display scaling on all monitors. Go to Start >Settings > System > Display. For each display, under Scale & Layout, set the same Scale value for all displays. Next step We are working on a resolution and will provide more information when it is available.	Keyboard accessibility option If buttons or text are difficult to select with a mouse, you can use the keyboard to interact with the warning message: Press Tab to move keyboard focus between options. When an option is highlighted, press the Spacebar to select it.

Applies to: Windows 10 Enterprise LTSB 2016 and Windows 10 IoT Enterprise 2016 LTSB

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

• March 10, 2026—KB5078938 (OS Build 14393.8957)

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

• [Windows Configuration System (WinCS)] This update addresses an issue that affects Windows Configuration System (WinCS) on Windows 10, version 1607 and Windows Server 2016. Some WinCS components were missing. Because of this, you could not turn on Secure Boot using WinCS.

• [Remote Desktop] This update improves protection against phishing attacks that use Remote Desktop (.rdp) files. When you open an .rdp file, Remote Desktop shows all requested connection settings before it connects, with each setting turned off by default. A one-time security warning also appears the first time you open an .rdp file on a device. For more information, see Understanding security warnings when opening Remote Desktop (RDP) files.

• [Secure Boot] 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.

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 April 2026 Security Updates.

For more information about Windows 10, version 1607, see its update history page.

For information about Windows update terminology, see the article about the types of Windows updates and the monthly quality update types.

Known issues in this update

Warnings related to Remote Desktop might not display correctly

Symptoms	Workaround	Notes
After installing this update, the security warning that appears when opening Remote Desktop (RDP) files might not display correctly in some cases. This issue might occur when you use more than one monitor with different display scaling settings (for example, one display set to 100% and another set to 125%). When this happens, the warning window might show overlapping text or partially hidden buttons, which can make the message difficult to read or interact with.	To help the warning window display correctly, set the same display scaling on all monitors. Go to Start >Settings > System > Display. For each display, under Scale & Layout, set the same Scale value for all displays. Next step We are working on a resolution and will provide more information when it is available.	Keyboard accessibility option If buttons or text are difficult to select with a mouse, you can use the keyboard to interact with the warning message: Press Tab to move keyboard focus between options. When an option is highlighted, press the Spacebar to select it.​​​​​​​