[BUG] Cowork crashes with "Claude Code process exited with code 1" on every new session (macOS)

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?

Every new Cowork session crashes immediately with the error "Something went wrong — Claude Code process exited with code 1." The message is sent, then the error banner appears and no response is returned. This started happening today; it was working previously.[](url)

<img width="821" height="375" alt="Image" src="https://github.com/user-attachments/assets/91fc482c-e455-43dd-b6f0-d37f3e768c5c" />

What Should Happen?

When I open Cowork on macOS and send a message in a new session, Claude should process the message and return a response in the conversation, the same way it did before today. The Claude Code process should launch and stay running for the duration of the session instead of exiting immediately with code 1.

Error Messages/Logs

Steps to Reproduce

1. Open Claude Cowork on macOS
2. Start a new conversation
3. Send any message (e.g. "hi")
4. Error banner appears: "Something went wrong — Claude Code process exited with code 1"

Expected Behavior

The message should be sent and receive a response.

Actual Behavior

The Claude Code process crashes instantly with exit code 1. The error banner offers "Go back" and "Try again" buttons, but retrying produces the same crash.

Scope

• Happens on every new session, not intermittent
• Started today (previously working)

Troubleshooting Already Attempted

• Fully quit and relaunched the app
• Restarted the Mac
• Confirmed app is on the latest version
• Tried starting sessions in different project folders
• None of the above resolved the issue

Screenshot

[attach the screenshot of the error banner here]

Additional Context

This may be related to #46029 (Cowork sessions crashing with exit code 1) or #40540 (Desktop App SDK flag incompatibility). Happy to provide logs from ~/Library/Logs/Claude/ if helpful.

<img width="821" height="375" alt="Image" src="https://github.com/user-attachments/assets/4f05adde-72af-4f43-a638-f93439452827" />

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

Claude 1.3036.0 (cf521c) 2026-04-16T16:17:33.000Z

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_