Horizon VDI Stuck On Login Spinner After Windows 11 October 2026 Update

Horizon VDI Stuck On Login Spinner After Windows 11 October 2026 Update

After applying the latest Windows 11 October 2026 updates (primarily the October 13 Patch Tuesday cumulative update KB5127648 and related builds), users of Omnissa Horizon (formerly VMware Horizon) VDI environments are reporting that sessions hang indefinitely on the login spinner after password entry. The desktop never loads or eventually loads but is extremely slow.

This matches widespread reports in Horizon communities and Microsoft’s release health documentation for virtual desktop environments. The issue primarily affects Windows 11 versions 24H2, 25H2, and 26H2.

Symptoms

• Credentials are accepted, then the session sits on the “Welcome,” “Please wait,” or spinning progress indicator indefinitely.
• Grey or black screens after sign-in.
• Occasional hangs on messages such as “Please wait for the gpsvc” or “Local Session Manager.”
• More common with FSLogix-style profiles and NVIDIA vGPU configurations.
• Immediate temporary relief sometimes possible with Ctrl+Alt+Del or manually launching explorer.exe.

Root Cause

Two overlapping issues are involved:

1. An earlier regression (originating in late-August/September 2026 updates) caused Explorer.exe to fail to start or crash repeatedly in multi-user / virtual desktop environments (especially those using FSLogix), producing black screens. Microsoft addressed this in the October 13 updates (KB5127648).
2. KB5127648 itself introduced a new logon/boot hang (LogonUI / DirectComposition related) that is particularly visible in Horizon environments running NVIDIA vGPU drivers. The problem was already present in the September preview (KB5124010) in some cases.

Microsoft has provided Known Issue Rollback (KIR) options and later preview updates that mitigate the hang.

Immediate Workarounds (for affected sessions)

While the spinner is visible:

• Press Ctrl + Alt + Del. Many users report this unsticks the Welcome screen.
• If Task Manager can be opened (Ctrl + Shift + Esc):
  File → Run new task → type explorer.exe → OK.
  This is Microsoft’s documented temporary workaround for the related Explorer black-screen issue.

Recommended Fixes

1. Apply the Known Issue Rollback (KIR) — preferred when possible

KIR does not uninstall the Windows update. It selectively reverts only the specific non-security change that is causing the problem via a feature flag, leaving the rest of the update (including security fixes) intact.

• • Download the matching KIR .msi from Microsoft’s Windows release health page for your exact Windows 11 version (the black-screen/Explorer KIR is publicly documented; the LogonUI hang KIR was often supplied via Microsoft support cases).
  • Install the MSI (adds the administrative template).
  • Open Local Group Policy Editor (gpedit.msc) or deploy via domain GPO.
  • Navigate to: Computer Configuration → Administrative Templates → [KB… Issue … Rollback] → Windows 11, version …
  • Set the policy to Disabled (this activates the rollback of the bad change).
  • Run gpupdate /force and restart.

Community-reported registry equivalent that has resolved the LogonUI hang for some Horizon + NVIDIA environments:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Policies\Microsoft\FeatureManagement\Overrides]
"4172144782"=dword:00000000

Apply, then restart. Best applied on the golden image before recomposing the pool.  You can roll out a group policy registry update for dedicated VDI.

2. Uninstall KB5127648

The most straightforward temporary fix reported across Omnissa forums. Uninstall from the master image, rebuild/recompose, and test. Re-evaluate once a permanent fix is confirmed.

3. Install later updates

Some environments report that the October 28 preview update (KB5127936) resolves the hang. Check Windows Update or the Microsoft Update Catalog for builds later than the October 13 cumulative.

4. Additional checks

• • Update NVIDIA vGPU drivers and Horizon Agent / VMware Tools to the latest supported versions.
  • Review FSLogix configuration and consider profile reset testing on a single desktop.
  • Use Horizon Logon Monitor to identify where time is being spent in the logon process.
  • Confirm Windows build with winver and exact installed KBs.

Prevention / Golden Image Guidance

• Pilot October (and later) Windows updates on a test pool before broad deployment.
• Apply the relevant KIR policy to the golden image prior to installing the update if the hang is expected.
• Maintain current Horizon Agent, NVIDIA, and Tools versions consistent with the Omnissa interoperability matrix.
• Document the exact build and KB set that was validated.

References

• Microsoft Windows release health: “Devices might experience a black screen or desktop loading issues after sign-in” (resolved in KB5127648 and later).
• Omnissa Community threads on KB5127648 boot/logon hangs (especially those involving NVIDIA vGPU).
• Microsoft Known Issue Rollback documentation.