[BUG] Claude Desktop 1.3109.0.0 fails to launch on Windows 11 Pro 25H2 — root-cause candidate identified (HCS Invalid JSON document)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Subject: Claude Desktop 1.3109.0.0 fails to launch on Windows 11 Pro 25H2 — root-cause candidate identified (HCS Invalid JSON document)

Hi Claude Support / Engineering Team,

I'm reporting a persistent failure of Claude Desktop to launch on Windows 11 Pro 25H2. I've already completed extensive troubleshooting and have isolated what looks like the root-cause error from cowork-service.log. I'd appreciate engineering's help resolving it.

Summary

Claude Desktop consistently fails to launch with the generic error: "Claude Desktop failed to launch. Please check for updates and try again." The error appears a few seconds after launch. No window ever renders. No crash dump is generated in %LOCALAPPDATA%\CrashDumps (the process dies too early).

System

• OS: Windows 11 Pro 25H2
• Claude Desktop: Claude_1.3109.0.0_x64__pzs8sxrjxfjjc (MSIX)
• App ID: Claude_pzs8sxrjxfjjc!Claude
• WebView2 Runtime: 147.0.3912.72 (healthy)
• sfc /verifyonly: no integrity violations
• Virtual Machine Platform: enabled
• No NTFS compression on C:
• No COR_PROFILER / CORECLR_* env vars set
• Desktop Known Folder registry is correct and folder exists

Root-cause candidate found in cowork-service.log

On the last successful VM session (before this issue began), the log shows the VM shutdown failed with an HCS error indicating a corrupted VM configuration:

2026/04/19 12:06:09.842331 [VM] Graceful shutdown failed, forcing termination:
HcsShutdownComputeSystem failed with HRESULT 0x0/0x8037010d:
{"Error":-1070137075,
"ErrorMessage":"The virtual machine or container JSON document is invalid.",
"ErrorEvents":[{"Message":"The specified property query is invalid:
The virtual machine or container JSON document is invalid.
(0xC037010D, 'Invalid JSON document \'$\'').",
"Provider":"17103e3f-3c6e-4677-bb17-3b267eb5be57",
"EventId":11001}]}

Since then, every subsequent CoworkVMService start completes cleanly (Service ready. Listening on \\.\pipe\cowork-vm-service) but Claude Desktop still fails to launch. The service is healthy; the app-to-service handoff or the stored VM configuration is what's broken.

Also, every service startup logs:

Warning: failed to open service for recovery config: Access is denied.

Secondary signal

Application Event Log shows a .NET Runtime error (ID 1022) around each launch attempt:

.NET Runtime version 4.0.30319.0 - There was a failure initializing profiling API attach infrastructure. This process will not allow a profiler to attach. HRESULT: 0x80004005.

Unclear if related to the VM service or independent.

Troubleshooting already performed

1. Full MSIX uninstall + reinstall with manual deletion of %LOCALAPPDATA%\Packages\Claude_pzs8sxrjxfjjc, %LOCALAPPDATA%\AnthropicClaude, %APPDATA%\Claude, and %ProgramData%\Claude. Reinstalled as administrator. Same failure.
2. Full LocalCache wipe specifically to invalidate any cached VM JSON. Rebooted. Same failure.
3. Cowork VM bundle reset (stopped CoworkVMService, restarted vmcompute, deleted vm_bundles, restarted service). Same failure.
4. All MSIX services confirmed running (AppXSvc, StateRepository, InstallService).
5. All Hyper-V / VM services confirmed running (CoworkVMService, vmcompute, hvhost, vmms).
6. No orphan VMs registered in HCS.
7. Direct launch via Start-Process "shell:AppsFolder\Claude_pzs8sxrjxfjjc!Claude" — same failure.

Background context

Claude Desktop worked correctly for an extended period (including Cowork) after an in-place Windows 11 repair from ISO. The launch failure appeared after I recreated the user's Desktop Known Folder via a PowerShell command (the folder wasn't being resolved by some apps) and rebooted. Windows Search also temporarily failed to resolve documents at that time but self-resolved after a later reboot. Claude Desktop has not recovered.

What I'd like help with

• Confirm whether the Invalid JSON document '$' error from HCS is the root cause
• Advise on how to fully purge the stored VM configuration (if LocalCache + ProgramData\Claude + vm_bundles deletion isn't sufficient)
• Provide a verbose logging flag or debug build for Claude Desktop's early startup path
• Confirm whether there are known issues with Claude Desktop 1.3109.0.0 on Windows 11 Pro 25H2 following Known Folder recreation

I have full PowerShell transcripts and cowork-service.log available on request. Happy to run any additional diagnostics.

Thank you for looking into this.

Best regards,

What Should Happen?

open

Error Messages/Logs

Claude Desktop Failed to Launch

Steps to Reproduce

Open de app

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

1.

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

_No response_