[Windows] Codex Desktop 26.820.9563.0 launches only as background process with no GUI

Resolved 💬 2 comments Opened Aug 27, 2026 by hawkenlee Closed Aug 28, 2026

💡 Likely answer: A maintainer (github-actions[bot], contributor) responded on this thread — see the highlighted reply below.

Description

After updating Codex Desktop on Windows today (August 27, 2026), Codex no longer opens its GUI.

Launching Codex creates the background process successfully, but no application window appears. There is no visible error message.

The issue started immediately after updating to:

OpenAI.Codex_26.820.9563.0_x64__2p2nqsd0c76g0

Actual behavior

Launch Codex Desktop.
Codex processes appear in Task Manager.
No Codex window is created.
No visible error message appears.
The background process remains running.

Expected behavior

Codex Desktop should create and display its main application window after launch.

Diagnostics

Windows AppModel-Runtime confirms that the MSIX application launches successfully:

OpenAI.Codex_26.820.9563.0_x64__2p2nqsd0c76g0

Event ID: 201

The event reports LaunchProcess and confirms that a process for OpenAI.Codex_2p2nqsd0c76g0!App was successfully created.

Codex Desktop's own log contains:

2026-08-27T11:30:58.743Z info Launching app agentRunId=null allowDebugMenu=false allowDevtools=false allowInspectElement=false buildFlavor=prod enableSparkle=false enableUpdater=true nodeEnv=undefined packaged=true platform=win32
2026-08-27T11:30:58.951Z info Appshot hotkey inactive configured=true enabled=false platform=win32

There are no subsequent GUI initialization messages or errors in that log.

Windows Application Error log also does not show a Codex crash corresponding to the launch attempt.

Troubleshooting already attempted

Terminated all Codex processes and relaunched the application.
Rebuilt the Codex MSIX LocalCache by renaming the existing LocalCache directory and allowing Codex to create a new one.
Confirmed that the problem remains with a newly generated LocalCache.
Confirmed that the Codex runtime binaries are present under %LOCALAPPDATA%\OpenAI\Codex\bin\<runtime-id>\, including:
codex.exe
codex-code-mode-host.exe
codex-command-runner.exe
codex-windows-sandbox-setup.exe

The MSIX package itself launches successfully according to AppModel-Runtime, but the main GUI never appears.

Additional context

Before this update, Codex Desktop was able to display its GUI.

I had previously encountered a separate helper_unknown_error / sandbox-related terminal issue, but after today's update the current failure occurs earlier: the Codex Desktop GUI itself does not appear at all.

The current issue therefore appears to be a Desktop startup/window initialization problem introduced after updating to 26.820.9563.0.

Environment

OS: Windows
Codex Desktop: 26.820.9563.0
Package: OpenAI.Codex_26.820.9563.0_x64__2p2nqsd0c76g0
Installation type: Microsoft Store / MSIX
Architecture: x64
Date issue started: August 27, 2026

View original on GitHub ↗

2 Comments

github-actions[bot] contributor · 23 hours ago

Potential duplicates detected. Please review them and close your issue if it is a duplicate.

#41075
#41096
#41073
#41064
#41056

Powered by Codex Action

hawkenlee · 1 hour ago

Update — issue persists after Store update to 26.825.3734.0

The affected machine has now automatically updated from 26.820.9563.0 to:

OpenAI.Codex_26.825.3734.0_x64__2p2nqsd0c76g0

The same headless startup behavior persists: multiple ChatGPT.exe processes start from the Codex MSIX package, but no visible window is created.

Additional diagnostics / troubleshooting performed:

Confirmed the bundled cua_node runtime is fully extracted, not stuck in a .staging-* directory.
%LOCALAPPDATA%\OpenAI\Codex\runtimes\cua_node currently contains ~8,486 files totaling ~1.07 GB.
Killed all ChatGPT.exe processes whose executable path belongs to OpenAI.Codex_26.825.3734.0_x64__2p2nqsd0c76g0.
Re-registered the current MSIX package with Add-AppxPackage -DisableDevelopmentMode -Register <AppxManifest.xml> after clearing those processes. Registration completed successfully.
Relaunched via shell:AppsFolder\OpenAI.Codex_2p2nqsd0c76g0!App.
The problem remains: background ChatGPT.exe processes start, but there is still no window.
Codex CLI remains usable, including access to existing sessions.

This suggests the problem is not limited to 26.820.9563.0, not caused by incomplete cua_node extraction, and not fixed by a clean MSIX re-registration.

A newly reported issue, #41268, also documents Windows desktop failures persisting across an update to 26.825.3734.0, although its exact symptom is a browser/main-process crash loop rather than the persistent headless state seen here.