Microsoft Windows Updates Cause Black Screens for Virtual Desktop Users

Microsoft has confirmed that recent Windows updates are causing desktop loading failures, including black screens, for certain users. The issue is primarily affecting Azure Virtual Desktop (AVD) hosts that utilise FSLogix, a software solution used to accelerate user profile loading in virtualised environments.

Users affected by this issue may encounter a black screen immediately after signing in, preventing access to the desktop until the session is started manually. Additionally, application event logs may show frequent crashes of Windows Explorer.

Affected Windows Versions

The problem has been identified in the August 2026 preview updates and several subsequent releases. Specifically, the issue affects devices running KB5120996 (Windows 11 26H1), KB5120998 (Windows 11 24H2/25H2), and the September Patch Tuesday updates, which include KB5124008 and KB5122880.

This follows a separate issue earlier this month, where Microsoft addressed a bug in the KB5120998 update that wiped mouse and desktop settings on some Windows 11 systems.

Mitigation and Workarounds

For individual users requiring an immediate workaround, Microsoft recommends manually launching Windows Explorer. This can be achieved by opening the Task Manager via Ctrl+Shift+Esc, selecting ‘Run new task’, entering explorer.exe, and clicking OK.

Enterprise administrators can mitigate the issue across managed devices using the Known Issue Rollback (KIR) feature. KIR allows for the reversal of specific buggy updates without requiring a full uninstallation of the update package.

To resolve the issue on enterprise devices, administrators must install and configure the appropriate Group Policy and restart the affected devices:

• Windows 11, version 26H1: Apply KB5124006 Known Issue Rollback.
• Windows 11, version 25H2 and 24H2: Apply KB5124010 Known Issue Rollback.

Microsoft noted that these Group Policies will disable the specific changes causing the instability until a permanent resolution is included in a future Windows update.