[BUG] Cowork "Virtual Machine Platform not available" — yukonSilver unsupported on Windows 10 Home 22H2

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 tab shows "Virtualization is not available" error. Log shows yukonSilver not supported (status=unsupported) and rootfs.vhdx missing. VM never initializes.

What Should Happen?

Cowork should detect that Virtual Machine Platform is enabled and successfully start the VM workspace without errors.

Error Messages/Logs

yukonSilver not supported (status=unsupported), checking for stale bundle...
rootfs.vhdx missing

Steps to Reproduce

1. Install Claude Desktop on Windows 10 Home 22H2
2. Enable Virtual Machine Platform, Windows Hypervisor Platform, and Hyper-V via Windows Features (optionalfeatures)
3. Restart computer
4. Open Claude Desktop
5. Navigate to the Cowork tab
6. Error appears immediately: "Virtualization is not available"

Claude Model

None

Is this a regression?

I don't know

Last Working Version

Never worked

Claude Code Version

Not applicable — issue is with Claude Desktop app (Cowork tab)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Other

Additional Information

This appears to be the same platform detection bug reported in issues #29887 and #32004. The log at %APPDATA%\Claude\logs\cowork_vm_node.log repeatedly shows "yukonSilver not supported (status=unsupported)" — the VM never attempts to initialize. rootfs.vhdx is never created. All troubleshooting steps completed: all 3 virtualization features enabled, reinstalled Claude Desktop as administrator, restarted multiple times — issue persists.