[BUG] CoworkVMService — found in Disabled state, clean exit 0 after re-enabling, no diagnostic logs (matches #36801 signature)

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?

CoworkVMService was found in StartType=Disabled state on first inspection — not
the previously-documented Manual-startup issue (#27010, #24918). Re-enabling it
via direct registry edit (Set-Service was blocked with Access Denied even when
elevated) allows the service to start, but it then exits cleanly with
WIN32_EXIT_CODE 0 / SERVICE_EXIT_CODE 0 and returns to STOPPED state within
~3 seconds. No VM is ever created.

This matches the black-box failure signature in #36801, but with two additional
data points not in that report:

1. The service's StartType was Disabled, not Manual — unclear whether this was

set by the installer, a Windows Update, or something else.

1. There is zero diagnostic trail anywhere: no System or Application event log

entries referencing CoworkVMService or Claude, no cowork_vm_node.log file,
and no LocalState folder was ever created under
%LOCALAPPDATA%\Packages\Claude_pzs8sxrjxfjjc\ — suggesting the service never
got far enough in its init routine to write anything.

What Should Happen?

CoworkVMService should start reliably given: valid package registration (Ok),
valid binary signature, running dependencies, and correct StartType — or at
minimum should log a diagnostic reason for exiting.

Actual Behavior

Service starts, exits cleanly with code 0, returns to Stopped within seconds.
No error surfaced anywhere in Windows or in Claude's own logs.

Error Messages/Logs

Service starts, exits cleanly with code 0, returns to Stopped within seconds.
No error surfaced anywhere in Windows or in Claude's own logs.

Steps to Reproduce

1. Get-Service CoworkVMService → StartType: Disabled
2. Set-Service CoworkVMService -StartupType Manual → fails: Access is denied

(even from elevated PowerShell)

1. Set-ItemProperty -Path "HKLM:\SYSTEM\CurrentControlSet\Services\CoworkVMService"

-Name "Start" -Value 3 → succeeds, confirmed via Get-ItemProperty

1. Start-Service CoworkVMService → fails: "Cannot start service CoworkVMService

on computer '.'"

1. sc.exe query CoworkVMService → STATE: STOPPED, WIN32_EXIT_CODE: 0,

SERVICE_EXIT_CODE: 0

1. Confirmed StateRepository dependency is Running (not the blocker)
2. Confirmed cowork-svc.exe exists at

C:\Program Files\WindowsApps\Claude_1.20186.9.0_x64__pzs8sxrjxfjjc\app\resources\cowork-svc.exe
with a Valid Authenticode signature

1. Get-WinEvent (System and Application logs) → zero entries mentioning

CoworkVMService or Claude

1. No cowork_vm_node.log or any log file exists anywhere under

%APPDATA%\Claude\logs or %LOCALAPPDATA%\Claude\logs

1. No LocalState directory exists under

%LOCALAPPDATA%\Packages\Claude_pzs8sxrjxfjjc\ — suggesting the app/package
has never completed first-run initialization for Cowork

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Claude 1.20186.9 (69f150) 2026-07-14T05:52:31.000Z

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

WSL (Windows Subsystem for Linux)

Additional Information

claude-diagnostic-9dcf6749-20260715-0001.zip