[BUG] Cowork tab missing on Windows 11 Pro 25H2 — yukonSilver marked as unsupported despite Hyper-V enabled, no CoworkVMService conflict

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 missing

What Should Happen?

Cowork tab should not be missing

Error Messages/Logs

OS: Windows 11 Pro 25H2
Hyper-V: Was disabled, now enabled — still failing
CoworkVMService: Does not exist
2026-04-17 11:43:07 [info] [cleanupVMBundleIfUnsupported] yukonSilver not supported (status=unsupported), checking for stale bundle...
Steps taken: Multiple clean reinstalls, deleted all Claude app data folders including Claude-3p

Steps to Reproduce

OS: Windows 11 Pro 25H2
Hyper-V: Was disabled, now enabled — still failing
CoworkVMService: Does not exist
2026-04-17 11:43:07 [info] [cleanupVMBundleIfUnsupported] yukonSilver not supported (status=unsupported), checking for stale bundle...
Steps taken: Multiple clean reinstalls, deleted all Claude app data folders including Claude-3p

Claude Model

Sonnet (default)

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

Claude 1.3109.0 (35cbf6) 2026-04-16T20:32:01.000Z

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

_No response_