KB5072033: This update introduces a change in behavior in which WDS
Windows Server 2025Microsoft
January 13, 2026—KB5073379 (OS Build 26100.32230)
This cumulative update for Windows Server 2025 (KB5073379), includes the latest security fixes and improvements, along with non-security updates from last month’s optional preview release. To learn more about differences between security updates, optional non-security preview updates, out-of-band (OOB) updates, and continuous innovation, see Windows monthly updates explained. For information on Windows update terminology, see the different types of Windows software updates.
To view the latest updates about this release, visit the Windows release health dashboard or the update history page for Windows Server 2025.
Improvements
This security update contains fixes and quality improvements from KB5072033 (released December 9, 2025). The following summary outlines key issues addressed by this update. Also, included are available new features. The bold text within the brackets indicates the item or area of the change.
- [Compatibility] This update removes the following modem drivers: agrsm64.sys (x64), agrsm.sys (x86), smserl64.sys (x64) and smserial.sys (x86). Modem hardware dependent on these specific drivers will no longer work in Windows.
- [Networking (known issue)] Fixed: This update addresses an issue where you might experience RemoteApp connection failures in Azure Virtual Desktop (AVD) environments. This might occur after installing KB5072033.
- [Servicing (known issue] This update addresses an issue where devices that installed the out-of-band update (KB5070881) stopped receiving Hotpatch updates. Affected machines will resume Hotpatch updates after installing the January 2026 baseline update.
- [Secure Boot] Starting with this update, Windows quality updates include a subset of high confidence device targeting data that identifies devices eligible to automatically receive new Secure Boot certificates. Devices will receive the new certificates only after demonstrating sufficient successful update signals, ensuring a safe and phased deployment. - [Windows Deployment Services (WDS] This update introduces a change in behavior in which WDS will stop supporting hands-free deployment functionality by default. Detailed guidance for IT administrators is available in Windows Deployment Services (WDS) Hands‑Free Deployment Hardening Guidance.
- [WinSqlite3.dll] Fixed: The Windows core component, WinSqlite3.dll, has been updated. Previously, some security software might have detected this component as vulnerable.
