Cowork never works on Windows 11 Home — virtualization detection fails, then MSIX reinstall loses Cowork tab permanently

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?

Cowork has never worked on my Windows 11 Home system. It was originally installed and the tab was visible, but it always showed "Virtualization is not available — Claude's workspace requires Hyper-V, but the virtualization service isn't responding" — despite all system checks confirming virtualization is fully operational. The VM never attempted to initialize (no logs folder or VM files were ever created).
After attempting a clean reinstall to resolve this, things got worse: the MSIX package fails to register with HRESULT 0x80073CF6, and the installer silently falls back to installing without Cowork (no user prompt). The Cowork tab is now permanently gone. I can't even get back to the broken-but-visible state.
System verification (all confirmed via PowerShell):

Windows edition: Home (Core), build 26200
VirtualMachinePlatform: Enabled
HypervisorPlatform: Enabled
Microsoft-Hyper-V-All: Not available (expected on Home)
vmcompute service: Running
CoworkVMService: Was running before reinstall
systeminfo: VM Monitor Mode Extensions: Yes
Intel VT-x in BIOS: Enabled

Related issues: #27384, #27316, #29532, #27420, #29887, #25162

What Should Happen?

1. Cowork should detect that virtualization is active via VirtualMachinePlatform + HypervisorPlatform on Windows Home, not require full Hyper-V (Microsoft-Hyper-V-All)
2. The MSIX installer should successfully register the package, or at minimum prompt the user before silently falling back to a Cowork-less install
3. It should be possible to recover the Cowork tab after a failed install without getting stuck in a permanent no-Cowork state

Error Messages/Logs

Cowork tab error (before reinstall):
Virtualization is not available. Claude's workspace requires Hyper-V, but the virtualization service isn't responding. Restart your computer to resolve this.

MSIX install failure (from ClaudeSetup.log):
Standard install (not split-account), using AddPackage
Installing via AddPackage (current-user)...
MSIX installation failed: AddPackage failed: AddPackage failed with HRESULT 0x80073CF6
Elevation failed: elevated installer exited with code 1
ERROR dialog (with log path): Administrator access is required to install Claude with full features. You can try again or install without Cowork.

No Cowork logs exist — the Claude app data folder under LocalCache\Roaming\Claude\ only contained a ChromeNativeHost folder. No logs folder, no vm_bundles, no VM files were ever created.

Steps to Reproduce

1. Install Claude Desktop on Windows 11 Home (build 26200) with VirtualMachinePlatform and HypervisorPlatform enabled
2. Open Claude Desktop — Cowork tab shows "Virtualization is not available" despite services running
3. Uninstall Claude Desktop
4. Clean up: remove Claude package folder, temp files, run Get-AppxPackage Claude | Remove-AppxPackage -AllUsers
5. Reinstall from claude.ai/download
6. MSIX install fails with 0x80073CF6
7. All subsequent installs silently skip Cowork — only Chat and Code tabs appear, no prompt offered

Troubleshooting attempted (none resolved either issue):

• Enabled HypervisorPlatform (was disabled, now enabled)
• Multiple clean reinstalls with full cleanup
• wsreset.exe to reset Windows Store cache
• Re-registered all AppX packages
• sc.exe delete CoworkVMService
• Removed all Claude temp files and registry entries
• Ran installer as administrator (UAC elevation confirmed in logs)

Claude Model

None

Is this a regression?

No, this never worked

Last Working Version

Cowork was never functional, but the tab was visible in the version installed on 2026/03/03 (ClaudeSetup.log shows successful MSIX install that date).

Claude Code Version

N/A — this is Claude Desktop, not Claude Code CLI

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

The core problem appears to be twofold:

The app checks for full Hyper-V (Microsoft-Hyper-V-All) which doesn't exist on Windows Home, even though the lighter VirtualMachinePlatform + HypervisorPlatform can run VMs
Once the MSIX install fails once, the installer permanently falls back to no-Cowork installs with no way to recover