Claude is repeatedly flagging yukonSilver not supported (status=unsupported) and never booting the VM

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?

Claude is repeatedly flagging yukonSilver not supported (status=unsupported) and never booting the VM. Claude's internal platform detection incorrectly marks your system as incompatible even though your hardware and OS are fully capable. This is not something you can fix on your end — it's a bug in Claude Desktop itself. At this point, the right move is to report it directly to Anthropic so they can investigate your specific case.

• Windows 11 Pro, x64
• Hyper-V enabled and vmms service running
• The log output showing yukonSilver not supported (status=unsupported) repeating
• Claude 1.2773.0 (884b37) 2026-04-15T14:32:09.000Z

What Should Happen?

I should be able to access Cowork from Claude desktop

Error Messages/Logs

Steps to Reproduce

Open Claude Desktop and Cowork does not appear

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Claude 1.2773.0 (884b37) 2026-04-15T14:32:09.000Z

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_