[BUG] OAuth /login fails with ECONNREFUSED on Windows 11, fresh install, network confirmed OK

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?

Title: OAuth /login fails with ECONNREFUSED on Windows 11, fresh install, network confirmed OK

Environment:

• OS: Windows 11
• Claude Code: 2.1.143 (npm-global install)
• Node.js: v24.13.1
• Claude Desktop app: same ECONNREFUSED on Claude Code tab

Steps to reproduce:

1. Fresh install via npm install -g @anthropic-ai/claude-code
2. Run claude → "Welcome back!" banner displays correctly
3. Run /login → browser opens, OAuth completes on Anthropic side
4. Callback to localhost fails with OAuth error: ECONNREFUSED

Network diagnostics (all passing):

• curl https://api.anthropic.com/ → 404 with proper Anthropic ASCII logo response
• Test-NetConnection api.anthropic.com -Port 443 → TcpTestSucceeded: True
• ping 127.0.0.1 → 0% loss
• DNS: Cloudflare + Google (IPv4 + IPv6)
• No HTTPS_PROXY / HTTP_PROXY / ANTHROPIC_* env vars
• No custom URLs in .claude.json
• netsh excluded port ranges: only 50000-50059 (normal)

Also tested:

• Multiple browsers (Opera, Chrome) → same ECONNREFUSED on callback
• Removed .claude.json and .claude/ → re-init OK but /login still fails
• Both OAuth flow and desktop app "Claude Code" tab produce same error

Workaround in use: desktop app chat tab works fine, only /login flow and Claude Code tab affected.

What Should Happen?

to be able to use claude code

Error Messages/Logs

Steps to Reproduce

Steps to reproduce:

1. Fresh install via npm install -g @anthropic-ai/claude-code
2. Run claude → "Welcome back!" banner displays correctly
3. Run /login → browser opens, OAuth completes on Anthropic side
4. Callback to localhost fails with OAuth error: ECONNREFUSED

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

2.1.143

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_