[BUG] 403 issue

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?

Cowork fails with 403 "Request not allowed" every time a task is submitted. Regular Claude Desktop chat works perfectly on the same account.

What Should Happen?

Cowork should authenticate successfully and process tasks, just like regular chat does.

Error Messages/Logs

Failed to authenticate. API Error: 403 {"error":{"type":"forbidden","message":"Request not allowed"}}

Steps to Reproduce

1. Log in to Claude Desktop with claude.ai account (OAuth)
2. Open Cowork tab
3. Submit any task
4. Immediately get 403 "Request not allowed" error

Claude Model

Opus

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Claude 1.1.8629 (befdfc) 2026-03-24T22:13:01.000Z

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

Account email: huangshengli@gmail.com
Organization ID: 16738686-a7ae-41fe-8f78-b332d099d56c
Plan: Max
Claude Desktop chat works fine. Only Cowork returns 403.
Network: ClashX proxy, global mode, Taiwan node.