[Windows] Codex Desktop app fails to start after update with "Unable to locate the Codex CLI binary"

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

26.820.7780.0

What subscription do you have?

Plus

What platform is your computer?

win11 26200.9168

What issue are you seeing?

The Codex Desktop app fails to start immediately after updating to the latest version. A dialog box appears with the error:

"ChatGPT failed to start. Unable to locate the Codex CLI binary. Set CODEX_CLI_PATH or ensure the Electron resources include bin/codex."

The app cannot proceed beyond this dialog—only "Check for Updates" and "Quit" buttons are available.

Steps to reproduce:

1. Previously had Codex Desktop working normally on Windows with WSL2 mode enabled.
2. Updated the app to the latest version via the in-app update prompt.
3. After the update, the app restarted and showed this error.
4. The app never reaches the main interface.

What I have tried:

• Verified that Codex CLI works in WSL2: running codex --version outputs the correct version without errors.
• Set CODEX_CLI_PATH environment variable pointing to the WSL-installed binary.
• Completely exited all Codex processes via Task Manager and restarted.

Workaround found:

• Setting runCodexInWindowsSubsystemForLinux = false in %USERPROFILE%\.codex\config.toml allows the app to start, but this disables WSL integration, which is not acceptable as a permanent solution.

This appears to be a regression introduced in the latest Windows update. I have seen multiple reports from other users with the same issue after the recent update.

What steps can reproduce the bug?

1. Use Codex Desktop app on Windows with WSL2 mode enabled (runCodexInWindowsSubsystemForLinux = true in config.toml).
2. Update the app to the latest version (26.609.4994.0) via the in-app update prompt.
3. After the update completes, the app attempts to restart.
4. A dialog appears with the error: "Unable to locate the Codex CLI binary. Set CODEX_CLI_PATH or ensure the Electron resources include bin/codex."
5. The app cannot proceed past this dialog and never reaches the main interface.

Note: Codex CLI is installed and working correctly in WSL2. Running codex --version in WSL terminal outputs the expected version without errors.

This is not a code execution bug—it is an application startup regression. No code snippet is applicable as the app fails to launch entirely.

What is the expected behavior?

The Codex Desktop app should start normally after updating, with WSL2 integration continuing to work as it did in the previous version. The app should detect the Codex CLI binary correctly in the WSL environment and proceed to the main interface.

In the previous version, this worked perfectly with the exact same configuration, so the expected behavior is that the update does not break existing WSL functionality.

Additional information

No response

Reproduce the post-update startup path with WSL2 enabled and inspect the Electron resources/bin/codex lookup, CODEX_CLI_PATH handling, and %USERPROFILE%.codex\config.toml setting. Done means the updated Windows app starts with runCodexInWindowsSubsystemForLinux=true and reaches the main interface while locating the CLI binary.