Microsoft marked a Windows 11 black-screen and desktop-loading issue as mitigated through version-specific Known Issue Rollback (KIR) policies on September 24, 2026. The problem appears after sign-in and has been reported primarily on Azure Virtual Desktop (AVD) hosts using FSLogix, Microsoft’s profile-management software. For a session where the desktop does not load, users can start explorer.exe from Task Manager; administrators can configure the KIR policy matching their Windows version.
What Microsoft says is affected
Microsoft associates the issue with the August 2026 non-security preview updates and later updates. The listed symptoms include a black screen after sign-in, a desktop that fails to load automatically, and Windows Explorer crash entries in the Application event log. Microsoft says the issue has been observed primarily on AVD hosts using FSLogix and more often with some existing user profiles.
Microsoft lists Windows 11 24H2, 25H2, and 26H1 as affected client versions and lists no affected server platform. It identifies the originating preview updates as KB5120998 for 24H2 and 25H2, and KB5120996 for 26H1; both were dated August 27, 2026.
Match the KIR policy to the Windows version
Microsoft’s September 24 mitigation uses a version-specific Group Policy package. Administrators must install and configure the matching policy, then restart affected devices.
| Windows 11 version | Originating preview update | Matching KIR policy |
| 24H2 and 25H2 | KB5120998, August 27, 2026 | KB5124010 260924_20021 |
| 26H1 | KB5120996, August 27, 2026 | KB5124006 260924_20071 |
KIR disables the change associated with the issue while Microsoft works on a resolution for a future Windows update. On September 23, Microsoft’s FSLogix known-issues page had listed the issue as “In progress” for FSLogix 2210 hotfix 4 (2.9.8884.27471) or later; the Windows release-health pages listed the KIR mitigation the following day.
Start Explorer for the affected session
If the desktop does not appear after sign-in, press Ctrl+Shift+Esc to open Task Manager. Select Run new task, enter explorer.exe, and select OK. This starts the Windows shell for that session; it is a temporary workaround, separate from the administrator-configured KIR mitigation.
