[BUG] Windows: spawnSync bash ENOENT error after recent update - regression from working state

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?

Here's the sanitized version with your sensitive paths removed:

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Title: Windows: spawnSync bash ENOENT error after recent update - regression from working state

Environment:

• OS: Windows 10 (Version 10.0.22631.5768)
• Git version: 2.45.1.windows.1
• Git location: C:\Git\cmd\git.exe
• Bash location: C:\Git\bin\bash.exe (verified working)
• Updated Claude Code today via VSCode

Issue Description:
Claude Code was working perfectly until I updated it today via VSCode. Now I'm getting a consistent spawnSync "C:\Git\bin\bash.exe" ENOENT error when trying to use any file operations.

Error Details:

Error: spawnSync "C:\Git\bin\bash.exe" ENOENT
    at Object.spawnSync (node:internal/child_process:1120:20)
    at spawnSync (node:child_process:901:24)
    at execSync (node:child_process:982:15)
    at Nk (file:///C:/Users/[username]/AppData/Roaming/npm/node_modules/@anthropic-ai/claude-code/cli.js:755:1044)

syscall: 'spawnSync "C:\\Git\\bin\\bash.exe"'
path: '"C:\\Git\\bin\\bash.exe"'
spawnargs: ['-c', "cygpath -u 'C:\\Users\\[username]\\Documents\\[project-path]'"]

Verification that bash works manually:

C:\Users\[username]>"C:\Git\bin\bash.exe" --version
GNU bash, version 5.2.26(1)-release (x86_64-pc-msys)

C:\Users\[username]>"C:\Git\bin\bash.exe" -c "cygpath -u 'C:\Users\[username]\Documents\[project-path]'"
/c/Users/[username]/Documents/[project-path]

C:\Users\[username]>bash --version
GNU bash, version 5.2.26(1)-release (x86_64-pc-msys)

Analysis:
The issue appears to be with how Node.js spawnSync handles the quoted path "C:\\Git\\bin\\bash.exe". The exact same command works perfectly when executed manually, but fails when called through Claude Code's spawnSync mechanism.

Related Issues:
This appears similar to issues #95 and #48, but this is a regression - it was working before today's update.

Request:
This is blocking all Claude Code functionality on Windows. Could this be prioritized as it appears to be a recent regression affecting Windows users who were previously working fine?

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What Should Happen?

This appears similar to issues #95 and #48, but this is a regression - it was working before today's update.

Error Messages/Logs

Steps to Reproduce

I entered a prompt to fix some errors, then got this during the response.

I'll implement the comprehensive fix plan to resolve all the
physics simulation issues. Let me start by creating a todo
list and then systematically address each problem.

● Let me first examine the boiler_system.py to understand how
the CoalCombustionModel results should be integrated:
<ref *1> Error: spawnSync "C:\Git\bin\bash.exe" ENOENT
at Object.spawnSync (node:internal/child_process:1120:20)
at spawnSync (node:child_process:901:24)
at execSync (node:child_process:982:15)

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

1.0.111 (Claude Code)

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

VS Code integrated terminal

Additional Information

Troubleshooting with a claude web chat:

Yes, this is indeed a known issue with Claude Code on Windows!

I found several GitHub issues on the anthropics/claude-code repository specifically about Windows ENOENT errors with bash/spawnSync problems:

1. Issue #95: "Cannot interact with Claude Code interface on Windows" - shows similar ENOENT errors with bash spawning on Windows 11

1. Issue #48: "Error: spawn /bin/bash ENDENT failure" - shows the exact same type of spawnSync bash ENOENT error

The fact that you just updated Claude Code for VSCode today explains why this suddenly broke - this appears to be a regression introduced in a recent update.

What to do:

1. Report this specific issue to the Claude Code GitHub repository (https://github.com/anthropics/claude-code) mentioning:

• You updated Claude Code today and it broke
• Windows 10 with Git Bash working fine manually
• The specific spawnSync quoted path error
• Reference issues #95 and #48 as related

1. Potential temporary workarounds based on the issues:

• Try downgrading Claude Code to the previous version if possible
• Try running from WSL instead of native Windows (if you have it)
• Try running Command Prompt/PowerShell as Administrator

1. Check the official troubleshooting docs at docs.anthropic.com/en/docs/claude-code/troubleshooting which has Windows-specific guidance

This is definitely a known Windows compatibility issue that got worse with recent updates. You're not alone - multiple users are experiencing this exact problem!