[BUG] Cowork fails to start on Windows — "signature verification initialization failed: failed to get service executable path

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 has never worked on my Windows machine. The CoworkVMService starts but immediately crashes with a path
resolution error during signature verification. This has persisted across multiple versions and restarts since
February 2026.

Error from cowork-service.log:
Service error: signature verification initialization failed: failed to get service executable path: The system cannot
find the path specified.

The HCS/HCN subsystem initializes successfully (vmcompute.dll and computecore.dll load fine), but the service fails at
signature verification because it cannot resolve its own executable path.

The service executable exists at:
C:\Program Files\WindowsApps\Claude_1.1.7714.0_x64__pzs8sxrjxfjjc\app\resources\cowork-svc.exe

I suspect the MSIX virtual filesystem is preventing the service from resolving its own path via standard Windows APIs.

Environment:

• Windows 11 Home (10.0.26200)
• Claude Desktop 1.1.7714.0 (MSIX package, downloaded from claude.ai)
• VirtualMachinePlatform: Enabled
• HypervisorPlatform: Enabled
• Full Hyper-V: Not available (Windows Home edition)

Reproduction:

1. Install Claude Desktop on Windows 11 Home
2. Open Cowork tab
3. Service starts and immediately fails

Logs:
The error repeats on every startup attempt. Full log available in %APPDATA%\Claude\logs\cowork-service.log.

What Should Happen?

Cowork has never worked on my Windows machine. The CoworkVMService starts but immediately crashes with a path
resolution error during signature verification. This has persisted across multiple versions and restarts since
February 2026.

Error from cowork-service.log:
Service error: signature verification initialization failed: failed to get service executable path: The system cannot
find the path specified.

The HCS/HCN subsystem initializes successfully (vmcompute.dll and computecore.dll load fine), but the service fails at
signature verification because it cannot resolve its own executable path.

The service executable exists at:
C:\Program Files\WindowsApps\Claude_1.1.7714.0_x64__pzs8sxrjxfjjc\app\resources\cowork-svc.exe

I suspect the MSIX virtual filesystem is preventing the service from resolving its own path via standard Windows APIs.

Environment:

• Windows 11 Home (10.0.26200)
• Claude Desktop 1.1.7714.0 (MSIX package, downloaded from claude.ai)
• VirtualMachinePlatform: Enabled
• HypervisorPlatform: Enabled
• Full Hyper-V: Not available (Windows Home edition)

Reproduction:

1. Install Claude Desktop on Windows 11 Home
2. Open Cowork tab
3. Service starts and immediately fails

Logs:
The error repeats on every startup attempt. Full log available in %APPDATA%\Claude\logs\cowork-service.log.

Error Messages/Logs

Steps to Reproduce

Cowork has never worked on my Windows machine. The CoworkVMService starts but immediately crashes with a path
resolution error during signature verification. This has persisted across multiple versions and restarts since
February 2026.

Error from cowork-service.log:
Service error: signature verification initialization failed: failed to get service executable path: The system cannot
find the path specified.

The HCS/HCN subsystem initializes successfully (vmcompute.dll and computecore.dll load fine), but the service fails at
signature verification because it cannot resolve its own executable path.

The service executable exists at:
C:\Program Files\WindowsApps\Claude_1.1.7714.0_x64__pzs8sxrjxfjjc\app\resources\cowork-svc.exe

I suspect the MSIX virtual filesystem is preventing the service from resolving its own path via standard Windows APIs.

Environment:

• Windows 11 Home (10.0.26200)
• Claude Desktop 1.1.7714.0 (MSIX package, downloaded from claude.ai)
• VirtualMachinePlatform: Enabled
• HypervisorPlatform: Enabled
• Full Hyper-V: Not available (Windows Home edition)

Reproduction:

1. Install Claude Desktop on Windows 11 Home
2. Open Cowork tab
3. Service starts and immediately fails

Logs:
The error repeats on every startup attempt. Full log available in %APPDATA%\Claude\logs\cowork-service.log.

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude Desktop 1.1.7714.0 (MSIX package, downloaded from claude.ai)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_