[BUG] Cowork VM connection timeout on Windows ARM64 Snapdragon — Linux guest never responds after add_plan9_shares

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). The VM boots
successfully but the Linux guest OS never establishes a connection.
Claude waits 60 seconds then times out. This happens on every attempt
with a fresh bundle.

What Should Happen?

The Linux guest should initialize and respond to the host connection
after vm_boot, allowing Cowork to start normally.

Error Messages/Logs

2026-04-11 08:20:42 [info] [VM:steps] vm_boot completed (403ms)
2026-04-11 08:20:42 [info] [VM:steps] add_plan9_shares completed (5ms)
2026-04-11 08:20:53 [info] [VM:start] Still waiting for guest connection... 10192ms elapsed, 21 polls
2026-04-11 08:21:03 [info] [VM:start] Still waiting for guest connection... 20362ms elapsed, 41 polls
2026-04-11 08:21:13 [info] [VM:start] Still waiting for guest connection... 30564ms elapsed, 61 polls
2026-04-11 08:21:23 [info] [VM:start] Still waiting for guest connection... 40750ms elapsed, 81 polls
2026-04-11 08:21:33 [info] [VM:start] Still waiting for guest connection... 50960ms elapsed, 101 polls
2026-04-11 08:21:43 [error] [VM:start] Connection timeout, last completed step: add_plan9_shares
2026-04-11 08:21:43 [error] [VM:start] Startup failed: Error: VM connection timeout after 60 seconds

Steps to Reproduce

1. Install Claude Desktop v1.1617.0.0 (ARM64) on Windows 11 ARM64 (Snapdragon)
2. Sign in with a paid plan
3. Click the Cowork tab
4. Observe: "Failed to start Claude's workspace — VM connection timeout after 60 seconds"

Confirmed environment:

• VirtualMachinePlatform: Enabled
• CoworkVMService: Running
• Claude installed as ARM64 (confirmed via Get-AppxPackage)
• VM bundle complete (rootfs.vhdx ~9GB present)
• Microsoft-Hyper-V-All: unavailable on ARM64 (expected)
• VirtualizationFirmwareEnabled: False (expected on Snapdragon)
• Fresh bundle re-download does not fix the issue
• Issue persists across multiple reboots

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Claude Desktop v1.1617.0.0 ARM64 (This is Claude Desktop Cowork, not Claude Code CLI)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

The VM boots and completes all steps up to add_plan9_shares, but the
Linux kernel inside the VM never responds. No coworkd logs are generated
inside the VM, suggesting the guest OS never reaches initialization.

Asus Zenbook A14

Related issues: #40198, #30566, #30864