[BUG] Claude Desktop failed to launch on macOS 26.3

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?

App: Claude Desktop (latest)
macOS: 26.3 (Build 25D125)
Chip: Apple Silicon (MacBook Air)

Issue:
Claude Desktop fails to launch immediately after installation.
Error message: "Claude Desktop failed to Launch. We are so sorry,
Claude Desktop failed to launch. Please check for updates and try
again. If the issue persists, contact support."

Steps to reproduce:

1. Download latest Claude Desktop .dmg from claude.ai/download
2. Drag to Applications folder
3. Launch the app

What I tried:

• Fresh reinstall multiple times
• Cleared ~/Library/Application Support/Claude
• Cleared ~/Library/Caches/Claude
• sudo xattr -cr (Operation not permitted on all files)

Result: Same error every time. App never launches.

What Should Happen?

Claude Desktop should launch successfully and display the login screen.

Error Messages/Logs

Error dialog: "Claude Desktop failed to Launch. We are so sorry, 
Claude Desktop failed to launch. Please check for updates and try 
again. If the issue persists, contact support."

Terminal output from xattr attempt:
xattr: [Errno 1] Operation not permitted: '/Applications/Claude.app'
(repeated for all files in the app bundle)

sudo xattr -cr result after reinstall:
xattr: No such file: /Applications/Claude.app
(app crashes before fully installing to Applications)

macOS: 26.3 (Build 25D125)
Chip: Apple Silicon MacBook Air

Steps to Reproduce

1. Download latest Claude Desktop .dmg from claude.ai/download
2. Open .dmg and drag Claude to Applications folder
3. Launch Claude from Applications
4. Error dialog appears immediately: "Claude Desktop failed to Launch"
5. App never opens

Claude Model

None

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

N/A - never worked on macOS 26.3

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_