Microsoft has released the KB5065429 cumulative update for Windows 10 22H2 and Windows 10 21H2, with fourteen fixes or changes, including fixes for unexpected UAC prompts and severe lag and stuttering issues with NDI streaming software.

The Windows 10 KB5065429 update is mandatory as it contains Microsoft's September 2025 Patch Tuesday security updates, which fix two publicly disclosed zero-day vulnerabilities and 81 flaws.

Windows users can install this update by going into Settings, clicking on Windows Update, and manually performing a 'Check for Updates.'

However, as this update is mandatory, it will automatically start installing in Windows once you check for updates. To make this more manageable, you can schedule a time when your computer is restarted to finish the installation.

After installing this update, Windows 10 22H2 will be updated to build 19045.6332, and Windows 10 21H2 will be updated to build 19044.6332.

Windows 10 users can also manually download and install the KB5065429 update from the Microsoft Update Catalog.

What's new in Windows 10 KB5065429

As Windows 10 nears the end of its life in October 2025, Microsoft is mainly focusing on bug fixes and improvements to the operating system.

However, this cumulative update fixes two bugs: one that caused lag and stuttering in NDI streaming software, and another that caused unexpected UAC prompts.

The complete list of changes and fixes is listed below:

• [Input and Composition] Fixed: An issue with the Chinese Simplified Input Method Editor (IME). Some extended characters were showing as empty boxes.

• [App compatibility (known issue)] Fixed: Addresses an issue that caused non-admin users to receive unexpected User Account Control (UAC) prompts when MSI installers perform certain custom actions. These actions might include configuration or repair operations in the foreground or background, during the initial installation of an application.

  This issue could prevent non-admin users from running apps that perform MSI repairs, including Office Professional Plus 2010 and multiple applications from Autodesk (including AutoCAD). This fix reduces the scope for requiring UAC prompts for MSI repairs and enables IT admins to disable UAC prompts for specific apps by adding them to an allowlist. For more information, see Unexpected UAC prompts when running MSI repair operations after installing the August 2025 Windows security update.

• [File Server] New! This update enables auditing SMB client compatibility for SMB Server signing as well as SMB Server EPA. This allows customers to assess their environment and identify any potential device or software incompatibility issues before deploying the hardening measures that are already supported by SMB Server. For detailed guidance, see CVE-2025-55234 | Windows SMB Elevation of Privilege Vulnerability.

• [Common Controls] Fixed: An issue that affects how certain supplementary characters appear in Windows textboxes.

• [Input and Composition] Fixed: An issue with the Chinese Simplified Input Method Editor (IME). Some extended characters were shown as empty boxes.

• [Licensing] New! This update adds an opt-in feature for administrators to allow outbound network traffic from Windows 10 devices. With this enabled, AAD users who have a Windows 365 subscription and devices joined to Entra ID can check if they qualify for Extended Security Updates (ESU) once Windows 10 support ends.

• [Mobile Operator Profiles] Updated: Country and Operator Settings Asset (COSA) profiles.

• [Multimedia] Fixed: An issue where mf.dll failed to enumerate redirected web camera devices on Remote Desktop Services (RDS) environments.

• [Windows Hello] Fixed: An issue in which Narrator reads the incorrect name for the "Enhance Facial Recognition Protection" check box under the Facial Recognition setting.

• [Search pane] Fixed: An issue that might cause the Windows Search pane to not show the preview pane correctly.

• [Family Safety] Fixed: An issue where the "Ask to Use" approval flow was not being triggered for blocked apps. With this fix, the approval flow now appears as expected when a blocked app is accessed.

• [Portable Devices] Fixed: An issue where the Removeable Storage Access policy may not work properly.

• [Windows Backup for Organizations] New! Windows Backup for Organizations is now generally available! Experience seamless device transitions with enterprise-grade backup and restore. Whether you're refreshing your organization’s devices, upgrading to Windows 11, or deploying AI-powered PCs, this solution helps sustain productivity with minimal disruption, ensuring business continuity and organizational resilience.

Microsoft states that there are no known issues with this update.

A complete list of fixes can be found in the KB5065429 support bulletin and last month's KB5063842 preview update bulletin.