[BUG] Orphaned CoworkVMService blocks MSIX reinstall on Windows (0x80073CF6), leaving Claude Desktop uninstallable/unlaunchable

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?

Summary

After a Claude Desktop update on Windows, the app became completely unlaunchable
(icon present in Start Menu, but clicking it did nothing — no process, no window).
Uninstalling and reinstalling did NOT fix it, because the uninstaller leaves behind
an orphaned Windows service (CoworkVMService), which then causes every subsequent
MSIX registration to fail with 0x80073CF6.

Environment

• OS: Windows (x64)
• Claude Desktop: MSIX package Claude_1.20186.1.0_x64__pzs8sxrjxfjjc (installed

via the official installer from claude.ai/download)

Symptoms

1. Clicking Claude in Start Menu: nothing happens. No process appears in Task Manager.
2. Start-Process "claude://" → "找不到应用程序" (application not found) — the

protocol handler was never registered.

1. explorer.exe shell:AppsFolder\Claude_pzs8sxrjxfjjc!Claude → silently does nothing.
2. Re-registering the package reveals the root cause:
3. 5. Get-Service CoworkVMService shows the orphaned service (DisplayName "Claude",

Status Stopped) even after Remove-AppxPackage -AllUsers.

Additional friction

• sc.exe delete CoworkVMService fails with **Access Denied (error 5) even in an

elevated PowerShell** — the service ACL blocks administrators.

• The only working fix was deleting the service's registry key directly:

  Remove-Item "HKLM:\SYSTEM\CurrentControlSet\Services\CoworkVMService" -Recurse -Force

then rebooting, uninstalling the broken package, and reinstalling as administrator.

Expected behavior

• Uninstall should remove CoworkVMService (or the installer should detect/replace

a stale one).

• The installer should not leave the app in a half-installed state (package present,

entry points unregistered) when service registration fails — at minimum it should
surface an actionable error to the user.

Impact

This has recurred across multiple update cycles on my machine ("app won't launch
after update" three times now). Recovery requires manually editing HKLM service keys,
which is not reasonable for ordinary users.

What Should Happen?

Uninstalling Claude Desktop should remove CoworkVMService, and the installer should detect and replace a stale service instead of failing. If service registration fails, the installer should surface a clear, actionable error instead of leaving the app half-installed (package present but entry points unregistered, so clicking the icon silently does nothing). Recovery should never require manually deleting HKLM service registry keys.

Error Messages/Logs

Steps to Reproduce

Summary

After a Claude Desktop update on Windows, the app became completely unlaunchable
(icon present in Start Menu, but clicking it did nothing — no process, no window).
Uninstalling and reinstalling did NOT fix it, because the uninstaller leaves behind
an orphaned Windows service (CoworkVMService), which then causes every subsequent
MSIX registration to fail with 0x80073CF6.

Environment

• OS: Windows (x64)
• Claude Desktop: MSIX package Claude_1.20186.1.0_x64__pzs8sxrjxfjjc (installed

via the official installer from claude.ai/download)

Symptoms

1. Clicking Claude in Start Menu: nothing happens. No process appears in Task Manager.
2. Start-Process "claude://" → "找不到应用程序" (application not found) — the

protocol handler was never registered.

1. explorer.exe shell:AppsFolder\Claude_pzs8sxrjxfjjc!Claude → silently does nothing.
2. Re-registering the package reveals the root cause:
3. ## Summary

After a Claude Desktop update on Windows, the app became completely unlaunchable
(icon present in Start Menu, but clicking it did nothing — no process, no window).
Uninstalling and reinstalling did NOT fix it, because the uninstaller leaves behind
an orphaned Windows service (CoworkVMService), which then causes every subsequent
MSIX registration to fail with 0x80073CF6.

Environment

• OS: Windows (x64)
• Claude Desktop: MSIX package Claude_1.20186.1.0_x64__pzs8sxrjxfjjc (installed

via the official installer from claude.ai/download)

Symptoms

1. Clicking Claude in Start Menu: nothing happens. No process appears in Task Manager.
2. Start-Process "claude://" → "找不到应用程序" (application not found) — the

protocol handler was never registered.

1. explorer.exe shell:AppsFolder\Claude_pzs8sxrjxfjjc!Claude → silently does nothing.
2. Re-registering the package reveals the root cause:

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

1.20186.1.0 (Claude Desktop MSIX)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_