[BUG] Cowork "VM not supported (win32/x64)" on Windows 10 Pro with Hyper-V enabled #27330

Cowork tab shows "Virtualization is not enabled" error and VM never starts on Windows 10 Pro x64. Hyper-V is fully enabled and all services are running correctly, yet yukonSilver is marked as unsupported and the VM is skipped with VM not supported (win32/x64).

This appears related to #27010 and #25136, but those issues don't have a resolution for Windows 10 Pro.

Environment

Hyper-V & Services Status

All Hyper-V components are installed and running:

Service          Status   StartType
-------          ------   ---------
vmms             Running  Automatic
vmcompute        Running  Manual
CoworkVMService  Stopped  Automatic

Network configuration is correct:

NAT Rule:    cowork-vm-nat -> 172.16.0.0/24
Adapter:     vEthernet (cowork-vm-vnet) -> Status: Up
Forwarding:  IPv4 Enabled

Logs

cowork_vm_node.log (repeating pattern since Jan 2025)

2026-02-20 23:41:26 [info] [cleanupVMBundleIfUnsupported] yukonSilver not supported (status=unsupported), checking for stale bundle...
2026-02-20 23:41:30 [warn] [startVM] VM not supported (win32/x64), skipping
2026-02-20 23:41:30 [info] [Callbacks] Initializing VM event callbacks...
2026-02-20 23:41:30 [info] [VM] Loading vmClient (TypeScript) module...
2026-02-20 23:41:30 [info] [VM] Module loaded successfully
2026-02-20 23:41:30 [info] [Callbacks] VM event callbacks initialized
2026-02-20 23:41:36 [warn] [startVM] VM not supported (win32/x64), skipping

claude_vm_node.log

[info] [SwiftVM] Loading @ant/claude-swift module...
[error] [SwiftVM] Failed to load module: Error: Cannot find package '...\node_modules\@ant\claude-swift\js\index.js'

The @ant/claude-swift module has never been found in any Claude Desktop version on this machine (tested across v1.0.3218, v1.1.280, v1.1.351, v1.1.381, v1.1.3918).

Steps to Reproduce

1. Install Claude Desktop v1.1.3918 (MSIX) on Windows 10 Pro x64 (Build 19045)
2. Ensure Hyper-V is enabled (vmms, vmcompute running, HypervisorPresent=True)
3. Open Claude Desktop and click the Cowork tab
4. Error: "Virtualization is not enabled" - suggests enabling in BIOS (already enabled)

What I've Tried

• Running fix-cowork-full.ps1 (resets NAT, enables IP forwarding, sets service to Automatic)
• Full uninstall/reinstall as Administrator
• Manually starting CoworkVMService
• Creating NAT rules and enabling IP forwarding manually
• Verified Hyper-V via Get-CimInstance Win32_ComputerSystem -> HypervisorPresent: True

None of these resolve the core issue: yukonSilver platform detection rejects win32/x64 on Windows 10.

Expected Behavior

Cowork should work on Windows 10 Pro x64 with Hyper-V enabled, or at minimum the error message should clearly state that Windows 10 is not supported (instead of suggesting BIOS virtualization changes).

Suggested Fix

1. If Windows 10 Pro is supported: fix yukonSilver platform detection to accept win32/x64 on Windows 10 Pro with Hyper-V
2. If Windows 10 Pro is NOT supported: update the error message to say "Windows 11 required" instead of the misleading "Enable virtualization in BIOS"
3. Include @ant/claude-swift module in the MSIX package (currently missing)