[BUG] [BUG] Cowork tab missing - yukonSilver unsupported on Windows 11

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 is completely missing from Claude Desktop. Only Chat tab is visible.

OS: Windows 11
CPU: Intel Core Ultra 7 255H
Claude version: 1.3561.0.0
Plan: Pro
Virtualization: Enabled in Task Manager

Log from cowork_vm_node.log:
yukonSilver not supported (status=unsupported)
CoworkVMService status: Running

Steps tried:

• Full uninstall and reinstall
• Cleared cowork-vm folders
• Restarted CoworkVMService
• Rebooted
• Nothing worked

What Should Happen?

The Cowork tab should appear in Claude Desktop alongside Chat, for Pro subscribers.

Error Messages/Logs

2026-04-21 17:38:24 [info] [cleanupVMBundleIfUnsupported] yukonSilver not supported (status=unsupported), checking for stale bundle...
2026-04-21 17:38:44 [info] [VM] Loading vmClient (TypeScript) module...
2026-04-21 17:38:44 [info] [VM] Module loaded successfully

Steps to Reproduce

1. Install Claude Desktop on Windows 11
2. Sign in with Pro account
3. Open the app
4. Observe: only Chat tab is visible, Cowork tab is missing

Claude Model

None

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

1.3561.0.0

Platform

Other

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_