Codex Windows app fails to launch and crashes in chrome.dll

What version of the Codex App are you using (From “About Codex” dialog)?

26.611.8604.0

What subscription do you have?

Plus

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What issue are you seeing?

Codex for Windows fails to launch on Windows 11.

The process starts briefly (cursor spins for ~1-2 seconds) and then exits without showing any UI. No error dialog is displayed.

This affects both:

• Codex 26.611.8604.0
• Codex Beta 26.611.8273.0

Windows reports the package as healthy and installed correctly. Other Microsoft Store applications launch normally.

Crashpad dumps are generated on every launch. Analysis of the dump with WinDbg shows an access violation inside the bundled Chromium runtime:

EXCEPTION_CODE: c0000005
Failure.Bucket: INVALID_POINTER_READ_c0000005_chrome.dll
PROCESS_NAME: Codex.exe
IMAGE_VERSION: 149.0.7827.115

Faulting frame:
chrome!v8::Context::Exit+0x1b

The crash occurs before any UI is rendered.

What steps can reproduce the bug?

1. Install Codex from the Microsoft Store.
2. Launch Codex from the Start Menu.
3. Wait approximately 1-2 seconds.
4. No window appears and the process exits.

Reproduces 100% of the time.

Additional details:

• Stable and Beta builds both affected
• Reinstalling does not help
• Reset-AppxPackage does not help
• Re-registering AppxManifest does not help
• Deleting LocalAppData package state does not help
• Installing/repairing WebView2 Runtime does not help
• Installing Visual C++ Redistributables does not help
• Launching with Chromium flags does not help:

  --disable-gpu
  --disable-gpu-compositing
  --disable-features=Vulkan
  --disable-features=V8Maglev,V8Sparkplug
  --no-sandbox

The process exits silently in all cases.

What is the expected behavior?

Codex should launch normally and display the main application window.

Additional information

Investigation performed:

• Get-AppxPackage reports package status as OK.
• AppModel Runtime logs show Codex process creation followed by immediate container destruction.
• No Application Error event is generated.
• Crashpad dumps are generated under:

%LOCALAPPDATA%\Packages\OpenAI.Codex_2p2nqsd0c76g0\LocalCache\Roaming\Codex\web\Codex\Crashpad\reports

WinDbg analysis:

EXCEPTION_CODE: c0000005
Failure.Bucket: INVALID_POINTER_READ_c0000005_chrome.dll
IMAGE_VERSION: 149.0.7827.115

Stack trace begins:

chrome!v8::Context::Exit+0x1b
chrome!node::AsyncResource::CallbackScope::~CallbackScope
chrome!ChromeMain

Loaded modules appear clean with no obvious third-party overlay or antivirus DLL injection.

Crash dump files can be provided if needed.