[BUG] cowork-svc file lock persists after "resolved" fix in #66497

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?

This issue was marked as resolved and locked, but I'm still hitting it on
current versions.

Package versions affected: 1.37937.0.0 → 1.37937.1.0 → 1.37937.3.0
(recurs on every update)

Error: "Another program is using this file" —
C:\Program Files\WindowsApps\Claude_<version>_x64_...

Root cause (confirmed via resmon + Get-Process):
cowork-svc.exe stays running after Claude closes and holds a file handle
in the WindowsApps directory, blocking the update from completing.

Workaround: Stop-Process -Name cowork-svc -Force, then relaunch.
Has to be repeated on every single update.

Related: #66497

What Should Happen?

Claude Desktop should complete its self-update without leaving a stale
process handle. cowork-svc.exe should release its file lock on the
WindowsApps directory before the update attempts to relaunch, or Claude
should terminate it automatically during the update process.

Error Messages/Logs

Windows dialog: "Aktualnie inny program korzysta z tego pliku."
(Another program is using this file.)
Path: C:\Program Files\WindowsApps\Claude_<version>_x64__pzs8sxrjxfjjc

Steps to Reproduce

1. Have Claude Desktop running normally
2. Update becomes available and installs (version bumps, e.g. 1.37937.0.0 → 1.37937.1.0)
3. Claude attempts to relaunch after update
4. Windows shows "Another program is using this file" for the WindowsApps Claude path
5. Confirmed via Get-Process that cowork-svc.exe is still running and holding

a file handle in the WindowsApps directory (verified with Resource Monitor →
Associated Handles)

1. Workaround: Stop-Process -Name cowork-svc -Force, then relaunch manually
2. This recurs on every subsequent update (reproduced across three separate

updates: 1.37937.0.0, 1.37937.1.0, 1.37937.3.0)

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

N/A - this is Claude Desktop, not Claude Code CLI

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

Note: This bug is in Claude Desktop (the app), not Claude Code CLI.
This form's fields don't map cleanly to a Desktop bug, so some fields
above are marked N/A. Filing here because prior related reports for
this exact issue (#66497, #61115) were also filed in this repo.

#66497 was locked as "resolved" but the issue persists across
1.37937.0.0, 1.37937.1.0, and 1.37937.3.0.