[BUG] Hooks freeze input on non-C: drives (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?

Any hook — even echo ok — causes Claude Code to freeze at the input prompt when the working directory is on a non-C: drive (E:). The cursor appears but no keystrokes are accepted. Freeze lasts several minutes. Same hooks work perfectly on C: drive.

What Should Happen?

Hooks should execute and return without blocking input, regardless of which drive the working directory is on.

Error Messages/Logs

none

Steps to Reproduce

1. Add this to ~/.claude/settings.json:

```json
{
"hooks": {
"SessionStart": [{ "hooks": [{ "type": "command", "command": "echo ok", "timeout": 2 }] }]
}
}

1. Open terminal, navigate to any folder on E: drive (or any non-C: drive)
2. Run claude
3. Claude starts and shows prompt, but keyboard input is frozen

Note: The same config works fine on C: drive. Tested with all plugins disabled, no MCP servers,
clean session cache — only hooks trigger the freeze.

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.37

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

Ruled out during investigation:

• Not plugins (disabled all 5 — still frozen)
• Not MCP servers (tested directories with no .mcp.json — still frozen)
• Not session cache size (cleaned 706MB to 29MB — still frozen)
• Not the hook command (even echo ok freezes)
• Not a reboot issue (restarted PC — still frozen)
• Hook timeout is ignored (set to 2s, freeze lasts minutes)

E: drive is a local NTFS volume. Issue likely affects any non-C: Windows drive.