Cowork VM timeout on Windows ARM64 Snapdragon X processor

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 fails to start on Windows ARM64 Snapdragon X processor.
Every session shows "Starting session..." for 60 seconds then
displays "Failed to start Claude's workspace - VM connection
timeout after 60 seconds." The ARM64 installer also failed with
error code 0x80073CF6. The x64 installer ran but Cowork never
worked. Reinstalling did not fix the issue.

What Should Happen?

Cowork should successfully start a session and respond to tasks
on Windows ARM64 Snapdragon X hardware.

Error Messages/Logs

"Failed to start Claude's workspace - VM connection timeout after 60 seconds"
ARM64 install error: AddPackage failed with HRESULT 0x80073CF6

Steps to Reproduce

1. Install Claude Desktop on Windows ARM64 Snapdragon X device
2. Sign in with paid Max plan account
3. Click Cowork tab
4. Type any task and submit
5. Session shows "Starting session..." for 60 seconds
6. Error: "VM connection timeout after 60 seconds"

Claude Model

Opus

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

Claude Desktop (Cowork) - version unknown, latest install as of March 31 2026

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

Device: Lenovo laptop
Processor: Snapdragon X - X126100 (Qualcomm Oryon ARM64)
RAM: 16GB
Plan: Max
Both x64 and ARM64 versions of Claude Desktop were attempted.
ARM64 install failed with 0x80073CF6.
x64 installed but Cowork VM never started.