Codex Desktop 26.608 crashes on startup when Windows username contains non-ASCII characters

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

26.608

What subscription do you have?

ChatGPT Plus

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What issue are you seeing?

Codex Desktop 26.608 crashes immediately after startup on Windows when the Windows username contains non-ASCII characters.

Symptoms:

• Codex CLI works normally
• App Server works normally
• A blank/dark Codex window appears briefly and then exits
• No useful Windows Event Viewer errors are generated
• Crash dumps are generated

Investigation showed the crash occurs during bundled cua_node runtime installation. The startup path eventually reaches Node.js fs.cpSync / std::filesystem code and throws an Illegal byte sequence exception when the user profile path contains non-ASCII characters.

Example user profile path:

C:\Users\測試用戶\

The application exits before completing startup.

What steps can reproduce the bug?

1. Create a Windows account whose username contains non-ASCII characters (for example: 測試用戶).
2. Install Codex Desktop 26.608.
3. Launch Codex Desktop.
4. Observe that the application briefly shows a window and then exits.

Workaround:

1. Locate the bundled resources\cua_node runtime.
2. Manually copy it into the expected runtime directory:

%LOCALAPPDATA%\OpenAI\Codex\runtimes\cua_node\<hash>

1. Launch Codex again.

After pre-populating the runtime directory, Codex starts successfully because the runtime installation step is skipped.

Unfortunately I do not have a minimal standalone reproduction beyond the startup sequence above.

What is the expected behavior?

Codex Desktop should start successfully regardless of whether the Windows username contains ASCII or non-ASCII characters.

The bundled runtime installation process should correctly handle Unicode paths and should not crash when the Windows profile directory contains Chinese, Japanese, Korean, Cyrillic, or other non-ASCII characters.

Additional information

Crash dump analysis pointed to the runtime/update installation flow.

The issue appears related to Node.js fs.cpSync / std::filesystem path handling during cua_node runtime installation.

After manually pre-populating the expected runtime directory, Codex launches normally and no new crash dumps are generated.

Platform:
Microsoft Windows NT 10.0.26200.0 x64

Codex Version:
26.608