[BUG] Claude Desktop (MSIX, Windows 11): orphaned claude process objects accumulate across sessions, eventually blocking launch — only a reboot clears them

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?

from Claude:
What's wrong

On the MSIX build, claude process objects survive session teardown and accumulate over days. After roughly ten days, nine orphans had built up from distinct sessions. New launches then start, log Not main instance, returning early from app ready, and exit without creating a window. Later launches stopped logging at all.

The orphans are unkillable from user-mode. Both Stop-Process -Force and taskkill /F /T fail, with taskkill reporting:

ERROR: The process with PID 10800 (child process of PID 33956) could not be terminated.
Reason: There is no running instance of the task.

That message indicates the tasks are already gone but the kernel process objects persist — consistent with leaked handles. Processes from the current session terminated cleanly in the same command; only the aged ones resisted. A reboot cleared all of them and the app launched normally.

Environment

Windows 11, x64
Claude Desktop 1.24012.9.0 (MSIX), Claude_1.24012.9.0_x64__pzs8sxrjxfjjc
Node 24.18.0, CCD 2.1.219
Package Status: Ok, IsPartiallyStaged: False, entry point present (Claude → app\Claude.exe)
vmcompute and hns both Running

Process list at failure

Id Name StartTime
10800 claude 7/29/2026 5:38:33 AM
24504 claude 7/28/2026 2:53:10 PM
36648 claude 7/27/2026 8:07:47 AM
47284 claude 7/30/2026 1:53:15 PM
57128 claude 8/6/2026 4:38:45 AM
58480 claude 7/27/2026 2:19:43 PM
60136 claude 7/27/2026 8:15:48 AM
72172 claude 7/28/2026 4:27:03 AM
73160 claude 7/31/2026 1:49:22 PM
80600 claude 7/31/2026 8:54:40 PM
136344 claude 8/6/2026 4:38:55 AM
193116 claude 8/6/2026 4:41:01 AM

Each orphan has a distinct parent PID; the three from 8/6 share parent 13908 and all terminated successfully.

main.log

2026-08-03 05:31:39 [info] Starting app { appVersion: '1.24012.9', isPackaged: true, platform: 'win32', arch: 'x64', nodeVersion: '24.18.0' }
2026-08-03 05:31:39 [info] [CCD] Initialized with version 2.1.219
2026-08-03 05:31:39 [info] Not main instance, returning early from app ready
2026-08-05 05:34:53 [info] Starting app { ... }
2026-08-05 05:34:53 [info] Not main instance, returning early from app ready
2026-08-05 05:34:53 [info] [update-restart] Detected nav-restore marker, launching normally
2026-08-05 05:34:53 [info] [update-restart] Detected nav-restore marker, launching normally
2026-08-05 05:34:53 [info] [stealth-relaunch] Loaded navigation history (4 entries, active=3)
2026-08-05 05:34:53 [info] [stealth-relaunch] Loaded navigation history (4 entries, active=3)

Note the duplicated [update-restart] and [stealth-relaunch] lines — two processes writing concurrently, both concluding they aren't the primary. Launch attempts on 8/6 produced no log entries at all.

Expected: process objects released on session teardown; a launch with no live instance creates a window.

Also worth noting: log path on the MSIX build is virtualized to %LOCALAPPDATA%\Packages\Claude_pzs8sxrjxfjjc\LocalCache\Roaming\Claude\logs\, not %APPDATA%\Claude\logs\. Troubleshooting docs pointing at the latter send people to a stale directory.

What Should Happen?

Process objects are released on session teardown. A launch with no live instance creates a window.

Error Messages/Logs

Steps to Reproduce

1. Use Claude Desktop over several days, closing the window with the X rather than quitting from the tray.
2. Allow at least one auto-update to occur during that period.
3. Periodically run: Get-Process claude | Format-Table Id,StartTime

Observe entries with StartTime from previous days accumulating.

1. Once several have accumulated, launch Claude Desktop. Processes appear in Task Manager but no window opens.
2. Attempt Get-Process claude | Stop-Process -Force, then taskkill /PID <id> /F /T. Aged PIDs cannot be terminated.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

1.24012.9.0

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

Two [update-restart] and two [stealth-relaunch] lines are logged for the same timestamp — two processes writing concurrently, both concluding they are not the primary.

Separately: on the MSIX build the log path is virtualized to
%LOCALAPPDATA%\Packages\Claude_pzs8sxrjxfjjc\LocalCache\Roaming\Claude\logs\
not %APPDATA%\Claude\logs\. Troubleshooting guidance pointing at the latter sends people to a stale directory.