Windows Codex app 26.609.3341.0 exits silently on launch

Summary

The Windows Codex app does not launch at all.

The app is installed and registered, but when I try to launch it, no window appears. It seems to create an AppModel-Runtime process/container and then exits silently.

The in-app /feedback command cannot be used because the Codex app never opens.

Environment

• OS registry output:

• ProductName: Windows 10 Home
• DisplayVersion: 25H2
• CurrentBuild: 26200
• UBR: 8655
• Codex app: Microsoft Store version
• Codex version: 26.609.3341.0
• Store ID: 9PLM9XGG6VKS
• AppID: OpenAI.Codex_2p2nqsd0c76g0!App
• WebView2 Runtime: Microsoft Edge WebView2 Runtime 149.0.4022.62 installed
• Security software: ESET

What happens

Launching Codex from any of the following does not show a window:

• Start menu
• Microsoft Store
• Administrator launch
• Direct launch via shell:AppsFolder

Direct launch command used:

explorer.exe shell:AppsFolder\OpenAI.Codex_2p2nqsd0c76g0!App

Result:
The app exits silently before showing any window.

Diagnostics

winget list Codex confirms the app is installed:

Codex  9PLM9XGG6VKS  26.609.3341.0  msstore

Get-StartApps | Where-Object {$_.Name -like "*Codex*"} shows:

Codex  OpenAI.Codex_2p2nqsd0c76g0!App

AppModel-Runtime logs show that the Codex process/container is created and then destroyed.

Windows Application event log does not show a clear Codex crash error.

Reliability Monitor previously showed Microsoft Store / Windows Update install failures for OpenAI.Codex:

0x80073CF9
0x80073D02

Logs

A sandbox.log exists, but it appears to be from an older backup and not from the current launch failure:

C:\Users\<USER>\.codex_backup_20260612\.sandbox\sandbox.log
LastWriteTime: 2026/06/02 14:39:07
Size: 81038 bytes

No new usable sandbox log appears to be generated for the current launch failure.

Troubleshooting already attempted

I already tried:

• Rebooting Windows multiple times
• Repairing the app from Windows settings
• Uninstalling and reinstalling Codex from Microsoft Store
• Running wsreset.exe
• Updating Microsoft Store apps
• Closing Claude, Chrome, Edge, and other potentially conflicting apps before reinstalling
• Installing Microsoft Edge WebView2 Runtime 149.0.4022.62
• Renaming/backing up %USERPROFILE%\.codex
• Renaming/backing up %LOCALAPPDATA%\Packages\OpenAI.Codex_2p2nqsd0c76g0
• Re-registering the app package using AppxManifest.xml
• Temporarily disabling ESET real-time file system protection
• Trying both normal launch and administrator launch

Expected behavior

The Codex Windows app should open normally.

Actual behavior

The app remains installed and registered, but exits silently before showing any window.

Because the app does not launch, I cannot use the in-app /feedback command or generate a feedback session ID.

Please investigate whether Codex 26.609.3341.0 has a Windows app launch issue, Microsoft Store package issue, or runtime/dependency compatibility issue.