[ERROR] Error streaming, falling back to non-streaming mode: Connection error.

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?

With CLAUDE_CODE_MAX_RETRIES=1, it resets instantly on attempt 1. With the default budget it retries 15x and either hangs for minutes or eventually errors.

What I ruled out (all tested, none changed the result)

• Phone hotspot on the same machine → works perfectly. Home Wi-Fi → resets every time. Same laptop, same session.
• curl.exe -I https://api.anthropic.com → instant clean 404.
• Streamed POST to /v1/messages via curl (dummy key) → instant clean 401 invalid x-api-key. Same network, same moment Claude Code was resetting.
• IPv6 disabled on the Wi-Fi adapter → no change.
• ipconfig /flushdns → no change.
• Malwarebytes (Free; all real-time/web protection already off) quit → no change.
• Native install and npm install → identical failure (different HTTP stacks, same result).
• claude --settings "{}" --strict-mcp-config -p "hi" (no plugins, no MCP, no statusline) → no change.
• claude doctor → "No installation issues found."
• UNDICI_NO_H2=1 (force HTTP/1.1) → no change.

Diagnosis
Network path and auth are provably healthy — curl (including a streamed POST) succeeds over the exact same home Wi-Fi, and the same machine works flawlessly on a phone hotspot. The failure is specific to the Claude Code client on this machine + home network, survives a full client swap and a config-stripped run, and only affects the streaming connection.

Working CF-RAY (from the successful curl): a29139ea0923dd26-YUL (Cloudflare Montréal edge)

Appears related to the existing Windows ECONNRESET cluster: #13657, #62045, #83994.

What Should Happen?

Claude Code should maintain a working streaming connection to api.anthropic.com whenever the same machine and network can reach the API by other means — as demonstrated here by curl (including a streamed POST to /v1/messages) succeeding over the identical home Wi-Fi, and by Claude Code working flawlessly on a phone hotspot from the same laptop. Instead, the streaming connection is reset (ECONNRESET) on every request over the home network.

Error Messages/Logs

Steps to Reproduce

Steps to reproduce

1. On Windows 11, run Claude Code on a home Wi-Fi connection: claude -p "hi"
2. Observe API Error: Unable to connect to API (ECONNRESET) on every request.
3. Confirm the network path is healthy from the same shell: curl.exe -I https://api.anthropic.com returns an instant 404, and a streamed POST to /v1/messages (with a dummy key) returns an instant 401.
4. Connect the same machine to a phone hotspot and run claude -p "hi" again → succeeds every time.
5. Switch back to home Wi-Fi → resets return immediately.

To make failures surface instantly instead of retrying: set CLAUDE_CODE_MAX_RETRIES=1 (or $env:CLAUDE_CODE_MAX_RETRIES = "1" in PowerShell) before step 1.

Claude Model

Not sure / Multiple models

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.1.226

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_