Previously, we reported that Microsoft urged everyone: “Don’t put off the September update.As a result, after many people did as they were told and updated,Instead, the computer began to experience various problems one after another.Microsoft later also acknowledged that this update caused multiple issues, including Remote Desktop being unable to connect, USB audio devices having no sound, and Explorer crashing immediately after login; on Reddit, many AMD graphics card users also reported black screens, driver timeouts, and crashes.
To address this, Microsoft quickly released an emergency patch update, KB5129195, outside its regular schedule to first resolve several of the confirmed issues. However, the AMD graphics card anomaly was not included in this patch and remains unresolved; Microsoft said it needs more data to further identify the root cause.
Image source: Windows Latest
Microsoft has urgently released KB5129195 to fix Remote Desktop, WSL shared folders, and some USB audio issues.
According to foreign media Windows Latest According to reports, Microsoft recently urgently released an out-of-band (off-schedule) cumulative update, KB5129195, for Windows 11 24H2 and 25H2; after installation, the version becomes Build 26100.9457 and 26200.9457.
Image source: Windows Latest
This is a mandatory update, so it will be downloaded automatically through Windows Update. After installation, you can go to Settings → System → About to check whether the version number ends in 9457.
Image source: Windows Latest
According to Microsoft’s official documentation, KB5129195 fixes three issues and one security vulnerability.
- Remote Desktop Services (RDS): After installing the September update, some users experience connection failures outright, while others get stuck on the “Please wait Remote Desktop configuration” screen when signing in and cannot continue; it may even cause the entire server side to become unresponsive. This KB5129195 has fixed the related issues.
- Hyper-V: After an update, Linux virtual machines may fail when mounting host shared folders through Plan9. This issue sounds fairly technical, but one clearly affected example is Anthropic’s Claude Cowork. Its Windows workspace uses this type of Linux virtual environment and host disk sharing mechanism, so after the September update it cannot properly access local disks and may even throw the “Failed to run Claude Cowork workspace” error.
- USB Audio Class 1.0 audio devices: After the update, multi-channel mode may not work properly, and settings including 8-channel and 3D audio may stop working. KB5129195 has also fixed this issue.
On the security vulnerability front, this update further patches CVE-2026-62721. The issue lies in the Windows User-Mode Power Service (UMPS). An attacker who can already execute code on the computer could manipulate power management requests to elevate privileges to SYSTEM.
Microsoft had actually already patched CVE-2026-62721 in its August 11 security update, but later discovered that the fix was incomplete, so KB5129195 adds further protection this time.
However, not everything was fixed this time either. Regarding an unresolved Explorer.exe crash after login, Microsoft employee Jason Parker took to Reddit to ask users who can reproduce the issue to provide full memory dumps, and said the September Windows update involved a wide range of changes and more data was needed to determine the root cause.
Among the unfixed issues, AMD graphics cards are probably the hardest part. The models reported under the earlier Reddit post include the RX 6600, RX 7700 XT, RX 7800 XT, RX 7900 GRE, RX 7900 XTX, and even the newly released RX 9070 XT. There are also many symptoms: they don’t only occur while gaming—even during regular desktop use or when opening a browser, the screen can suddenly go black or the system can crash.
Some users reported that the problem goes away after removing KB5124008, but it is not effective in all cases, and removing the update also means losing the September security patches. So far, there is no confirmed effective solution.
Source: KOCPC Chinese