Windows browser sandbox fails to initialize: SetTokenInformation(TokenDefaultDacl) failed: 1344

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

26.803.5235.0

What subscription do you have?

Plus

What platform is your computer?

Windows 11 Pro, build 26200.8973, x64

What issue are you seeing?

Summary

ChatGPT Work cannot initialize either the built-in browser or the Chrome extension on Windows. Both fail before opening a tab.

Error

windows sandbox: runner failed during SpawnChild: SetTokenInformation(TokenDefaultDacl) failed: 1344

Environment

• Windows 11 build 26200.8973
• ChatGPT Desktop package 26.803.5235.0
• ChatGPT Work
• Built-in browser and Chrome extension are both affected

What I tried

• Reinstalled the ChatGPT Desktop app
• Restarted the PC
• Ran DISM /Online /Cleanup-Image /RestoreHealth
• Ran sfc /scannow (it repaired corrupted Windows files)
• Confirmed Windows Defender has no relevant block events
• Tested in a new Work chat, including without a linked folder

The issue still happens.

Local sandbox evidence

The local sandbox log reports:

setup refresh: processed 117 write roots (read roots delegated); errors=[]

Feedback ID

no-active-thread-019fe417-588c-7e81-96ff-af746d6dcf27

What steps can reproduce the bug?

Feedback ID: no-active-thread-019fe417-588c-7e81-96ff-af746d6dcf27

What is the expected behavior?

The built-in browser should initialize and open https://example.com in a new tab.

Additional information

Reproduction: start a new ChatGPT Work chat without attaching a folder, then ask it to open https://example.com with the built-in browser.

Actual result: the browser fails before opening a tab. Both the built-in browser and Chrome extension are affected.

Error: SetTokenInformation(TokenDefaultDacl) failed: 1344

Windows 11 Pro build 26200.8973
ChatGPT Desktop package 26.803.5235.0