Codex.app fails to launch after upgrade on macOS: RBSRequestErrorDomain Code=5 / NSPOSIXErrorDomain Code=163

Environment

• OS: macOS 10.15.7 Catalina
• Device: Intel Mac
• App: Codex.app
• Install location: /Applications/Codex.app
• Modification: The app bundle was not modified manually.

Problem

After upgrading Codex.app, the application cannot be opened.

Running:

open /Applications/Codex.app

returns:

The application cannot be opened for an unexpected reason, error=Error Domain=RBSRequestErrorDomain Code=5 "Launch failed." UserInfo={NSLocalizedFailureReason=Launch failed., NSUnderlyingError=0xbccc28720 {Error Domain=NSPOSIXErrorDomain Code=163 "Unknown error: 163" UserInfo={NSLocalizedDescription=Launchd job spawn failed}}}

Expected behavior

Codex.app should launch normally after upgrading.

Actual behavior

Codex.app fails to launch immediately.

Notes

The app bundle was not manually modified. This happened after upgrading.

Please let me know what logs or diagnostic commands I should provide.