[BUG] Windows: ECONNRESET on first Claude Code prompt despite working HTTPS

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?

claude-code-bug-report.md

claude-code-bug-report.md

Environment

• OS: Windows 11
• Claude Code CLI: 2.1.268
• VS Code extension: Claude Code 2.1.269
• Node.js: v22.13.0
• Installation: official winget/native Windows installer

Problem

Claude Code fails already on the first prompt with:

Connection dropped (ECONNRESET)

The issue occurs in multiple projects and also when using a mobile hotspot.

Network tests

The following work correctly:

• DNS resolution for api.anthropic.com
• TCP connection to port 443
• TLS handshake
• curl request to https://api.anthropic.com/
• Node HTTPS request to https://api.anthropic.com/

No HTTP_PROXY, HTTPS_PROXY or custom CA environment variables are configured.

Debug log

The Claude Code debug log contains:

• mTLS: Creating HTTPS agent with custom certificates
• Policy limits: fetch failed (http) from api.anthropic.com - socket hang up
• API REQUEST /v1/messages
• API error: Connection error
• ECONNRESET
• CCRClient: unknown certificate verification error
• SSETransport: socket connection was closed unexpectedly

The issue is reproducible before any project-specific operation is performed.

What Should Happen?

Claude Code should maintain a stable connection and complete the first prompt successfully. The request should not fail with ECONNRESET, socket hang up, or certificate verification errors. Bootstrap, policy checks, MCP registry, CCR/SSE streaming, and /v1/messages should complete normally, with retries only for genuine transient failures.

Error Messages/Logs

Steps to Reproduce

1. Install Claude Code CLI 2.1.268 on Windows.
2. Sign in with a valid Claude account.
3. Open PowerShell in any project directory.
4. Start Claude Code with:

``powershell
claude --debug --debug-file "$env:TEMP\claude-debug.log"
``

1. Enter a minimal prompt such as:

``text
ciao
``

1. Wait for the request to start.
2. The connection fails immediately or after a short delay with:

``text
Connection dropped (ECONNRESET)
``

1. Claude retries the request repeatedly and eventually reports a connection error.
2. Repeat the same test in a different project or using a mobile hotspot. The issue remains reproducible.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.268 (Claude Code)

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_