[BUG] PowerShell installer crashes with Bun ENOTCONN error on Windows 11

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?

Environment:

• OS: Windows 11
• Terminal: PowerShell
• Command used: & ([scriptblock]::Create((irm https://claude.ai/install.ps1))) latest

Error:
panic(main thread): Unexpected error
ENOTCONN: Transport endpoint is not connected (open())
Bun v1.2.23 crashes during installation

Expected behavior:
Installation should complete successfully as documented

Actual behavior:
Bun crashes with ENOTCONN error

What Should Happen?

The installation should complete successfully and Claude Code should be installed without any Bun crashes or ENOTCONN errors.

Error Messages/Logs

Setting up Claude Code...
============================================================
Bun v1.2.23 (cf136713) Windows x64 (baseline)
Windows v.win11_dt
CPU: sse42 avx avx2
Args: "C:\Users\username\.claude\downloads\claude-2.0.9-win32-x64.exe" "install" "stable"
Features: Bun.stderr(2) Bun.stdin(2) Bun.stdout(2) jsc spawn standalone_executable
Builtins: "bun:main" "node:assert" "node:async_hooks" "node:buffer" "node:child_process" "node:constants" "node:crypto" "node:domain" "node:events" "node:fs" "node:fs/promises" "node:http" "node:https" "node:module" "node:net" "node:os" "node:path" "node:path/win32" "node:perf_hooks" "node:process" "node:querystring" "node:stream" "node:string_decoder" "node:timers/promises" "node:tls" "node:tty" "node:url" "node:util" "node:zlib" "undici" "ws" "node-fetch" "node:inspector" "node:http2"
Elapsed: 520ms | User: 531ms | Sys: 78ms
RSS: 0.34GB | Peak: 0.34GB | Commit: 0.43GB | Faults: 83252 | Machine: 16.52GB

panic(main thread): Unexpected error
ENOTCONN: Transport endpoint is not connected (open())
oh no: Bun has crashed. This indicates a bug in Bun, not your code.

To send a redacted crash report to Bun's team,
please file a GitHub issue using the link below:

 https://bun.report/1.2.23/e_1cf13671Az//v//B+kjgXisjljB2wm7iB__0jg40CA0eNoLzUutKEhNLklNUUgtKsov4pKONsiVjjY2zHX18w9x9vfzgwgY5VqBGAohRYl5xQX5RSUKqXkpBfmZeSUKmcUKefklCsn5eXkQg0CqNfILUvM0NDVBmgCMOyDn


✅ Installation complete!

Steps to Reproduce

1. Open PowerShell on Windows 11
2. Run the installation command:

& ([scriptblock]::Create((irm https://claude.ai/install.ps1))) latest

1. Bun starts installing but crashes immediately with ENOTCONN error
2. Installation fails

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.0.8

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Windows Terminal

Additional Information

_No response_