[BUG] Cowork Windows - HcnCreateEndpoint fails with Element not found + macOS diagnostic code running on Windows

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?

Summary

Cowork on Windows fails to start with two distinct issues:

1. HcnCreateEndpoint fails with "Element not found" - The VM boots successfully but fails to create a network endpoint, even with a clean HNS state (no existing cowork networks).
2. macOS diagnostic code runs on Windows - After the network failure, the diagnostic routine attempts to execute macOS-only binaries (/sbin/ifconfig, /usr/sbin/scutil, /usr/sbin/kextstat, /usr/bin/pgrep, /usr/bin/log) on Windows, all failing with ENOENT.

Environment

• Claude Desktop Version: 1.1.2998.0 (MSIX, Windows Store)
• Platform: Windows 11 Pro x64, Build 10.0.26200
• CPU: 13th Gen Intel Core i9-13900HX
• RAM: 32 GB
• Network: Wi-Fi (Killer Wi-Fi 6E AX1690i), Fritz!Box router, DNS 192.168.178.1
• Hyper-V: Enabled, all services running (vmcompute, vmms, hns)
• Subscription: Max

Steps to Reproduce

1. Clean install Claude Desktop 1.1.2998 on Windows 11 Pro x64
2. Enable Hyper-V, confirm services running
3. Open Claude Desktop, click Cowork tab
4. VM files download successfully (rootfs.vhdx 2.2GB, vmlinuz, initrd)
5. VM configures Windows VM service successfully
6. VM boot fails at network endpoint creation

Error Logs

Primary Error (cowork_vm_node.log):

[VM:start] Beginning startup, bundlePath=...claudevm.bundle
[VM:start] Bundle version: 0ae58222a1f34cf74c74ce47cc717a82a4eb0f25
[VM:steps] download_and_sdk_prepare completed (4ms)
[VM:steps] load_swift_api completed (0ms)
[VM:start] smol-bin.vhdx copied successfully
[VM:start] Configuring Windows VM service...
[VM:start] Windows VM service configured
[VM:start] VM boot failed: failed to create network endpoint: HcnCreateEndpoint failed: hr=0x80070490, error={"Success":false,"Error":"Element not found.","ErrorCode":2147943568}

macOS Diagnostics Running on Windows:

[networkDiagnostics] === Comprehensive macOS Diagnostics ===
[networkDiagnostics] Failed to run /sbin/ifconfig: Error: spawn /sbin/ifconfig ENOENT
[networkDiagnostics] Failed to run /usr/sbin/scutil: Error: spawn /usr/sbin/scutil ENOENT
[networkDiagnostics] Failed to run /usr/sbin/kextstat: Error: spawn /usr/sbin/kextstat ENOENT
[networkDiagnostics] Failed to run /usr/bin/pgrep: Error: spawn /usr/bin/pgrep ENOENT
[networkDiagnostics] Failed to run /usr/bin/log: Error: spawn /usr/bin/log ENOENT

Earlier session (before clean HNS state) showed API unreachable:

[VM:start] Startup complete, total time: 8939ms
[VM] API reachability: PROBABLY_UNREACHABLE
[VM] API reachability: UNREACHABLE
[VM:network] API is unreachable

Troubleshooting Already Attempted

• Clean reinstall of Claude Desktop
• Deleted %APPDATA%\Claude\vm_bundles and re-downloaded all VM files
• Verified Hyper-V enabled (Get-WindowsOptionalFeature confirms State: Enabled)
• Verified vmcompute, vmms services running
• Removed all stale HNS networks (Get-HnsNetwork shows only Default Switch)
• Removed stale cowork-vm-nat virtual switch via Remove-HnsNetwork
• Disabled all unused network adapters (Bluetooth, ExpressVPN TAP/TUN/OpenVPN, extra Ethernet/Wi-Fi)
• Uninstalled McAfee antivirus (was blocking rootfs.vhdx download)
• Removed and deleted HNS.data file
• Ran as Administrator (elevation_type: full)
• Rebooted multiple times
• Manually set DNS to 8.8.8.8 on Wi-Fi adapter

Expected Behavior

Cowork should create an HNS network and endpoint, boot the VM, and connect to the Claude API.

Additional Notes

• The "Element not found" error occurs even when no cowork HNS network exists, suggesting Claude's VM service fails to create the network before attempting the endpoint.
• The macOS diagnostic code running on Windows (/sbin/ifconfig, /usr/sbin/scutil, etc.) confirms the Windows port has platform-detection issues.
• Related issues: #25205, #25144, #25136, #24918

What Should Happen?

Cowork should create an HNS network and endpoint, boot the Linux VM, and connect to the Claude API successfully. The diagnostic code should use Windows-appropriate commands (ipconfig, netsh, etc.) instead of macOS binaries.

Error Messages/Logs

[VM:start] VM boot failed: failed to create network endpoint: HcnCreateEndpoint failed: hr=0x80070490, error={"Success":false,"Error":"Element not found.","ErrorCode":2147943568}

[networkDiagnostics] === Comprehensive macOS Diagnostics ===
[networkDiagnostics] Failed to run /sbin/ifconfig: Error: spawn /sbin/ifconfig ENOENT
[networkDiagnostics] Failed to run /usr/sbin/scutil: Error: spawn /usr/sbin/scutil ENOENT
[networkDiagnostics] Failed to run /usr/sbin/kextstat: Error: spawn /usr/sbin/kextstat ENOENT
[networkDiagnostics] Failed to run /usr/bin/pgrep: Error: spawn /usr/bin/pgrep ENOENT
[networkDiagnostics] Failed to run /usr/bin/log: Error: spawn /usr/bin/log ENOENT

Steps to Reproduce

1. Clean install Claude Desktop 1.1.2998 on Windows 11 Pro x64 (Build 26200)
2. Enable Hyper-V, confirm vmcompute and vmms services running
3. Open Claude Desktop, click Cowork tab
4. VM files download successfully (rootfs.vhdx 2.2GB, vmlinuz, initrd)
5. VM configures Windows VM service successfully
6. VM boot fails at network endpoint creation with HcnCreateEndpoint "Element not found"
7. Diagnostic routine runs macOS commands on Windows (all fail with ENOENT)

Note: In an earlier session where the HNS network existed, the VM booted but reported API reachability: UNREACHABLE (likely DNS issue from stale/disconnected network adapters being picked up by the HNS network). After cleaning all HNS state, the error changed to "Element not found" suggesting the app cannot create the HNS network from scratch.

Extensive troubleshooting performed:

• Removed all stale HNS networks and cowork virtual switches
• Disabled all unused network adapters (Bluetooth, ExpressVPN TAP/TUN/OpenVPN, extra Wi-Fi/Ethernet)
• Uninstalled McAfee (was silently blocking rootfs.vhdx download - 0 byte temp file)
• Deleted HNS.data and rebooted
• Ran as Administrator
• Multiple clean reinstalls and reboots

Claude Model

None

Is this a regression?

No, this never worked

Last Working Version

N/A - Cowork never worked on this Windows machine

Claude Code Version

1.1.2998 (Claude Desktop with Cowork)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

Network Adapter Context

This machine has multiple network adapters (Killer Wi-Fi 6E, Bluetooth, ExpressVPN TAP/TUN/OpenVPN adapters, multiple Killer Wi-Fi phantom adapters). ExpressVPN has been uninstalled and most adapters disabled, but the issue persists even with only Wi-Fi + Default Switch active.

Two Distinct Failure Modes Observed

Mode 1 (with existing HNS cowork-vm-nat network):
VM boots, network connects, SDK installs, but API reachability = UNREACHABLE. Likely caused by VM inheriting DNS from wrong adapter (similar to #25144).

Mode 2 (after removing all cowork HNS state):
VM fails to boot entirely with HcnCreateEndpoint "Element not found" (0x80070490). The app appears unable to create the HNS network from scratch.

McAfee Note

McAfee antivirus was silently blocking the rootfs.vhdx download (0-byte .tmp file). Had to fully uninstall McAfee before the 2.2GB download would complete. This may affect other users.

Related Issues

• #25205 (API unreachable + Cowork tab disappears)
• #25144 (DNS from disconnected adapter)
• #25136 (yukonSilver marked unsupported + CoworkVMService conflicts)
• #24918 (API unreachable on Windows 11 Home)