Windows 10 KB5066198 (OS Build 19045.6396) Preview released
Microsoft has recently released KB5066198 (OS Build 19045.6396) Preview for various versions of Windows 10, including Home and Pro, version 22H2, Enterprise Multi-Session, Education, and IoT Enterprise. This update is part of the ongoing efforts to improve and stabilize the operating system.To successfully install this preview update, users are advised to apply KB5015684, which will allow them to update their systems to Windows 10, version 22H2. The provided update contains all the necessary fixes and quality improvements from the previous release, specifically KB5065429 (OS Builds 19044.6332 and 19045.6332), which was made available on September 9, 2025.
One of the significant features included in this update is support for IT administrators to implement hardening measures for Server Message Block (SMB). This enhancement is designed to improve security by allowing administrators to deploy necessary hardening measures for SMB. For detailed guidance on implementing these changes, users can refer to CVE-2025-55234|Windows SMB Elevation of Privilege Vulnerability.
Additionally, the update addresses a known issue that affected some users after installing the August 2025 Windows security update (KB5063709). This issue caused delays or uneven audio and video performance issues when using Network Device Interface (NDI) to stream or transfer feeds between PCs. The update includes a fix for this problem.
This release also resolves two previously known issues:
The first issue involved connectivity with the SMBv1 protocol, which could cause users difficulties when trying to connect to shared files and folders while using the Server Message Block (SMB) v1 protocol over NetBIOS on TCP/IP (NetBT). This issue arose after installing update KB5065429.
The second issue affected Windows Autopilot deployment, specifically when configuring the Enrollment Status Page (ESP). In some cases, users might observe that the ESP doesn't load during the Out-of-Box Experience (OOBE) when using Windows Autopilot to deploy Windows 10, version 22H2.
It's worth noting that if you have installed earlier updates on your device, only the new updates contained in this package will be downloaded and installed. For further information about Windows update terminology or an overview of Windows 10, version 22H2, please refer to the corresponding articles.
Microsoft has also released the servicing stack update (KB5066411) - 19045.6389. This update integrates the most recent servicing stack update (SSU) for your operating system with the most recent cumulative update (LCU). SSUs are designed to improve the reliability of the update process, mitigating potential issues while installing updates.
The servicing stack is an essential component that installs Windows updates, and this update makes quality improvements to it. For more information about SSUs or Servicing Stack Updates (SSU), please see the relevant articles on servicing stack updates and frequently asked questions.
September 25, 2025—KB5066198 (OS Build 19045.6396) Preview
September 25, 2025—KB5066198 (OS Build 19045.6396) Preview - Microsoft Support
