codex-windows-sandbox-setup.exe Application Error

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

Version 26.616.51431 • Released 20 Jun 2026

What subscription do you have?

Plus

What platform is your computer?

Microsoft Windows NT 10.0.26100.0 x64

What issue are you seeing?

When I start the Codex Application it prompts me to 'Install the required sandbox update':

<img width="780" height="182" alt="Image" src="https://github.com/user-attachments/assets/8edc012a-9fe4-4fdf-903f-df290a74d9fd" />

When I click on update it requests admin permission. I enter credentials with Admin permission.

It then errors with:

<img width="439" height="245" alt="Image" src="https://github.com/user-attachments/assets/187cf902-5569-4027-8913-9d29708baad9" />

The Codex app now reports:

<img width="743" height="94" alt="Image" src="https://github.com/user-attachments/assets/142ea572-2b8e-4ae2-9bfc-08e34cc174f3" />

Retries do not work.

What steps can reproduce the bug?

1. Launch the Codex on on Windows 11.
2. Click the button to update the sandbox.

What is the expected behavior?

The codex-windows-sandbox-setup.exe does not error.

Additional information

_No response_