[Windows] Relaunch to Update fails with "Another program is using this file" (MSIX file lock 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?

Clicking "Relaunch to Update" fails with Windows dialog: "另一程序正在使用此文件" (Another program is using this file). Claude does not relaunch automatically. Install path: C:\Program Files\WindowsApps\Claude_1.11187.4.0_... (MSIX package)

What Should Happen?

Claude should wait for the old process to fully release file locks before launching the new version.

Error Messages/Logs

Windows system dialog error: "另一程序正在使用此文件。" (Another program is using this file.)

Dialog path shown: C:\Program Files\WindowsApps\Claude_1.11187.4.0_...

Steps to Reproduce

See update notification in Claude Code on Windows
Click "Relaunch to update"
Claude closes
Windows error dialog appears: "另一程序正在使用此文件"
Claude does not restart

Claude Model

None

Is this a regression?

No, this never worked

Last Working Version

_No response_

Claude Code Version

1.11187.4.0

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Windows Terminal

Additional Information

<img width="458" height="168" alt="Image" src="https://github.com/user-attachments/assets/5d5321a0-8ebb-4548-8538-e39f1eb5ed3c" />