codex - 💡(How to fix) Fix WSL app-server remains active after switching back to Windows and breaks Windows sandbox setup

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

Local logs/package paths observed during debugging referenced: - OpenAI.Codex_26.519.2081.0_x64 - release=26.519.21041

What subscription do you have?

Pro

What platform is your computer?

Windows, using Codex Desktop with both Windows Agent Environment and WSL Agent Environment.

What issue are you seeing?

After switching Codex Desktop Agent Environment from Windows to WSL and then back to Windows, Windows sandbox setup stops working correctly.

When the UI is back on Windows, the local app-server still appears to be launched through WSL instead of the Windows native Codex executable. In the broken state:

• Desktop logs show the local app-server launched with:
  • spawnCommand=wsl.exe
  • executablePath=C:\Users<user>.codex\bin\wsl...\codex
• In the same run, Codex Desktop still calls:
  • windowsSandbox/readiness
  • windowsSandbox/setupStart
• windowsSandbox/setupStart is then repeated many times.
• Logs also show mixed WSL/Windows paths such as:
  • /mnt/c/...
  • /home/...
  • C:\home...

This makes it look like Codex Desktop has not fully switched the local app-server state back from WSL to Windows native mode before attempting Windows sandbox setup.

Deleting C:\Users<user>.codex temporarily recovers the app, but the problem reproduces again after switching Windows -> WSL -> Windows.

What steps can reproduce the bug?

1. Start Codex Desktop on Windows.
2. Use the Windows Agent Environment and confirm it works normally.
3. Switch Agent Environment to WSL.
4. Switch Agent Environment back to Windows.
5. Try to use Windows sandbox setup again.
6. Observe that Windows sandbox setup does not complete normally and may repeatedly attempt setup.

Observed after reproduction:

• C:\Users<user>.codex\config.toml still had: runCodexInWindowsSubsystemForLinux = true
• The latest Desktop log still showed the local app-server spawning via wsl.exe even though the UI had been switched back to Windows.

What is the expected behavior?

When Agent Environment is switched back from WSL to Windows:

1. Codex Desktop should fully restore the Windows native local app-server.
2. The local app-server should be launched with the Windows Codex executable, not wsl.exe.
3. Windows sandbox readiness/setup should run only against the Windows native app-server state.
4. The WSL selection state should not remain active after returning to Windows.

Additional information

Debugging evidence from the same machine:

Broken state:

• Latest Desktop log showed: stdio_transport_spawned ... spawnCommand=wsl.exe executablePath=C:\Users<user>.codex\bin\wsl...\codex
• The same log showed: windowsSandbox/readiness repeated windowsSandbox/setupStart calls
• The same log showed WSL/Windows path mixing, including C:\home... failures.

Known-good state:

• After recovery, a normal Windows run showed: stdio_transport_spawned ... spawnCommand="...\WindowsApps...\codex.exe"

Windows sandbox itself does not appear to be permanently damaged:

• The Windows sandbox log contained successful setup entries such as:
  • WFP setup succeeded
  • setup refresh ... errors=[]
  • setup binary completed

Relevant persisted state observed in the broken state:

• C:\Users<user>.codex\config.toml contained: runCodexInWindowsSubsystemForLinux = true

Minimal recovery workaround found:

• Close Codex Desktop.
• Change this line in C:\Users<user>.codex\config.toml: runCodexInWindowsSubsystemForLinux = true to: runCodexInWindowsSubsystemForLinux = false
• Restart Codex Desktop.

This workaround is smaller than deleting the entire .codex directory, but it does not fix the underlying recurrence when switching Windows -> WSL -> Windows again.