Microsoft Releases Emergency Windows Updates to Fix Remote Desktop, Hyper-V, and USB Audio Issues
Microsoft has released emergency out-of-band Windows updates to resolve Remote Desktop Services (RDS) failures, Hyper-V problems, and multichannel USB audio issues caused by the September 2026 security updates.
The September Windows security updates caused Remote Desktop Services to become unstable on some supported Windows and Windows Server systems. Affected administrators reported failed RDP connections and sign-ins, while some servers became unresponsive.
Microsoft acknowledged the Remote Desktop problems after widespread reports from Windows administrators. In addition to RDP failures, related tools and components—including Microsoft Management Console (MMC), RDS Licensing Diagnostics, File Explorer, and the Windows Update settings page—could stop responding.
Emergency Windows updates fix Remote Desktop failures
Microsoft released several out-of-band updates on September 14, 2026, to address the Remote Desktop Services issues introduced by the September security updates.
The affected Windows Server updates include:
- Windows Server 2025: The issue was introduced by update KB5122871.
- Windows Server 2022: The issue was introduced by update KB5122882.
- Windows Server 2019, Windows Server 2022, and Windows Server 2025: Emergency updates are available through the Microsoft Update Catalog.
Microsoft previously provided Group Policy mitigations for affected Windows and Windows Server devices while it developed a permanent solution.
Some administrators reported that uninstalling the September security updates restored Remote Desktop functionality. However, removing those updates also removed the security fixes included in them, leaving systems exposed to the vulnerabilities addressed by the September release.
For Windows 11 26H1, update KB5129194 is available through Windows Update, Windows Update for Business, the Microsoft Update Catalog, and Windows Server Update Services (WSUS).
Microsoft also released the following updates to resolve RDS failures:
- KB5129195 for Windows 11 versions 24H2 and 25H2
- KB5129236 for Windows 10 versions 21H2 and 22H2
Windows updates also fix Hyper-V and multichannel audio problems
The emergency Windows 11 updates also resolve a Hyper-V issue affecting applications that use virtual machines managed by Host Computing Services (HCS).
When Plan 9 is used to share a Windows host folder with a Linux virtual machine, some applications may be unable to see or access the shared folder from within the guest operating system. The out-of-band updates address this problem.
Microsoft also fixed an issue affecting some USB Audio Class 1.0 devices when used with multichannel audio configurations, including 8-channel and 3D audio modes.
USB audio devices should continue to work normally in standard stereo mode. However, affected devices may fail when users switch to supported multichannel audio configurations.
Some USB audio issues remain unresolved
The emergency updates do not resolve every USB audio problem introduced by the September security updates.
Microsoft said that some USB Audio Class 1.0 devices may fail to launch or produce sound after installing the September 8, 2026, Windows security updates.
Reported symptoms include the following:
- Device Manager displays “This device cannot start (Code 10).”
- No audio output is available.
- The volume control is unresponsive or remains at zero.
- Windows sound settings are unresponsive or unavailable.
Microsoft said the remaining issue is limited to USB Audio Class 1.0 devices and confirmed that it is working on a fix.
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Source: www.bleepingcomputer.com