[BUG] Folder no longer exists. Please start a new session." — old chats broken, new chats hang on latest 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?

What's Wrong:
On macOS 26.3 (25D125), Claude Code is completely unusable after updating to the latest version:

Existing chats show: "Folder no longer exists. Please start a new session."
New chats just show the thinking spinner indefinitely and never load
Cowork and claude.ai work fine — this is isolated to the Claude Code desktop app

macOS: 26.3 (25D125)
Claude Code version: [run claude --version in terminal]

Additional Context:
Issue appears to be specific to the latest Claude Code version running on macOS 26.3. Full reinstall and complete data wipe did not resolve it, which suggests this is not a corrupted data issue but a compatibility problem between the latest Claude Code and macOS 26.3.

What Should Happen?

Expected Behavior: Chats load and new sessions start normally.
Actual Behavior: App is completely unusable. All existing chats fail, all new chats hang. Attempted full reinstall, cleared all Claude app data via terminal commands — issue persists. Only workaround is using claude.ai in browser.
Environment:

Error Messages/Logs

Steps to Reproduce

Steps to Reproduce:

Run latest Claude Code on macOS 26.3 (25D125)
Existing chats show "Folder no longer exists. Please start a new session."
Try creating a new chat — spinner runs indefinitely, never loads

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

What ever the previous verision to this was

Claude Code Version

Claude 1.1.3647 (8f7c53) 2026-02-19T15:02:19.000Z

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_