KB5066835

Symptoms

Some Digital TV and Blu-ray/DVD apps might not play protected content as expected after installing the August 29, 2025, Windows non-security preview update (KB5064081), or later updates.

Apps that use Enhanced Video Renderer with HDCP enforcement or Digital Rights Management (DRM) for digital audio might show copyright protection errors, frequent playback interruptions, unexpected stops, or black screens.

Streaming services are not affected. 

Workaround

​​​​​​​The non-security September 2025 Windows preview update (KB5065789) and later updates address problems affecting certain applications that use the Enhanced Video Renderer (EVR) with HDCP (High-bandwidth Digital Content Protection) enforcement. The non-security October Windows preview update (KB5067036) includes additional improvements to address problems affecting applications using Digital Rights Media (DRM) for digital audio.

Symptoms

After installing October 2025 security update (KB5066835), USB devices, such as keyboards and mice, do not function in the Windows Recovery Environment (WinRE). This issue prevents navigation of any of the recovery options within WinRE. Note that the USB keyboard and mouse continue to work normally within the Windows operating system.

Workaround

This issue is addressed in KB5070773.

Symptoms

After installing the non-security September update (KB5065789) for Windows 11, version 25H2, or the security October update (KB5066835) for Windows 11, version 24H2, server-side applications that rely on HTTP.sys might experience issues with incoming connections. As a result, Internet Information Services (IIS) websites might fail to load and display an error message such as “Connection reset – error (ERR_CONNECTION_RESET)” or a similar message. This includes websites hosted on http://localhost/ and other IIS connections.

This issue may result from various conditions, including internet connectivity, timing of update installation, and device restarts. It might not occur in all environments, even if the update is installed.

The following steps can help resolve this issue in environments where it's observed:

1. On the affected device, open Settings and go to Windows Update.

2. Select Start​​​​​ , type Check for updates, and Check for updates from the results. 

3. If updates are available, install them.

4. Restart your device.​​​​​​​

Workaround

This issue is addressed in KB5067036. 

Symptoms

After installing the August 2025 non-security preview update (KB5064081) or later updates, you might notice that the password icon is not visible in the sign-in options on the lock screen. If you hover over the space where the icon should appear, you’ll see that the password button is still available. Select this placeholder to open the password text box and enter your password. After entering your password, you can sign in normally.

Individuals using Windows Home or Pro editions on personal devices are very unlikely to experience this issue. This issue primarily affects enterprise or managed IT environments.

Workaround

This issue is mitigated using Known Issue Rollback (KIR).

For enterprise-managed devices managed by IT departments that have installed the affected update and encountered this issue, IT administrators can resolve it by installing and configuring the Group policy listed below. The special Group Policy can be found in Computer Configuration > Administrative Templates > <Group Policy name listed below>.

For information on deploying and configuring these special Group Policy, please see How to use Group Policy to deploy a Known Issue Rollback.

Group Policy downloads with Group Policy name:

• Download for Windows 11 version 24H2, Windows 11 version 25H2: Windows 11 24H2, Windows 11 25H2 and Windows Server 2025 KB5072033 251202_18051 Known Issue Rollback

Important: You will need to install and configure the Group Policy for your version of Windows to resolve this issue. You will also need to restart your device(s) to apply the group policy setting. Note that the Group Policy will temporarily disable the change causing this issue. 

We are working on a resolution in a future Windows update and will provide more information when it is available.