[BUG] Claude Desktop crashes on startup with EBADF rename error on Windows 11 25H2 (Build 26200) - MSIX sandbox filesystem conflict

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?

Claude Desktop fails to launch on Windows 11 25H2 (Build 26200) with an EBADF error when attempting an atomic write of git-worktrees.json. The app crashes immediately on every startup with no workaround available.The error occurs in Node.js renameSync when Claude Desktop tries to atomically write git-worktrees.json by creating a .tmp file and renaming it to the final path. The rename operation fails with EBADF: bad file descriptor.Root cause analysis: Claude Desktop is distributed as an MSIX package (Microsoft Store). On Windows 11 25H2 (Build 26200), the MSIX virtualized filesystem intercepts %APPDATA% and redirects it to %LOCALAPPDATA%\Packages\Claude_pzs8sxrjxfjjc\LocalCache\Roaming\Claude\. The Node.js renameSync call fails with EBADF within this virtualized filesystem environment, which appears to be a regression introduced in Build 26200.

What Should Happen?

Claude Desktop should launch successfully and be able to read/write its config files within the MSIX sandbox environment.

Error Messages/Logs

Error: EBADF: bad file descriptor, rename 'C:\Users\17419\AppData\Roaming\Claude\git-worktrees.json.tmp-31970270184d508b' -> 'C:\Users\17419\AppData\Roaming\Claude\git-worktrees.json'
{"errno":-4083,"code":"EBADF","syscall":"rename","path":"C:\\Users\\17419\\AppData\\Roaming\\Claude\\git-worktrees.json.tmp-31970270184d508b","dest":"C:\\Users\\17419\\AppData\\Roaming\\Claude\\git-worktrees.json"}
    at renameSync (node:fs:1018:11)
    at a (C:\Program Files\WindowsApps\Claude_1.1.6041.0_x64__pzs8sxrjxfjjc\app\resources\app.asar\.vite\build\index.js:98:15084)
    at Object.u [as writeFileSync] (C:\Program Files\WindowsApps\Claude_1.1.6041.0_x64__pzs8sxrjxfjjc\app\resources\app.asar\.vite\build\index.js:98:22168)
    at c._write (C:\Program Files\WindowsApps\Claude_1.1.6041.0_x64__pzs8sxrjxfjjc\app\resources\app.asar\.vite\build\index.js:106:41675)
    at set store (C:\Program Files\WindowsApps\Claude_1.1.6041.0_x64__pzs8sxrjxfjjc\app\resources\app.asar\.vite\build\index.js:106:40204)
    at new Z (C:\Program Files\WindowsApps\Claude_1.1.6041.0_x64__pzs8sxrjxfjjc\app\resources\app.asar\.vite\build\index.js:106:37953)
    at new c (C:\Program Files\WindowsApps\Claude_1.1.6041.0_x64__pzs8sxrjxfjjc\app\resources\app.asar\.vite\build\index.js:106:43986)
    at new ZOt (C:\Program Files\WindowsApps\Claude_1.1.6041.0_x64__pzs8sxrjxfjjc\app\resources\app.asar\.vite\build\index.js:756:5418)

Steps to Reproduce

Install Windows 11 25H2 (Build 26200) — either clean install or upgrade via KB5055456 enablement package
Install Claude Desktop from Microsoft Store (MSIX package, version 1.1.6041.0)
Launch Claude Desktop
App immediately crashes with the error dialog: "We're so sorry, Claude Desktop failed to launch. Please check for updates and try again."
Check logs — EBADF rename error on git-worktrees.json is present on every launch attempt

Claude Model

None

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

1.1.6041.0

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information