Windows Codex App terminal fails to launch external executables via normal PowerShell invocation, but .NET ProcessStartInfo works

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

OpenAI Codex desktop app package path indicates OpenAI.Codex_26.313.5234.0_x64__2p2nqsd0c76g0 (please confirm exact About dialog version if needed)

What subscription do you have?

Unknown / not sure from this session

What platform is your computer?

Microsoft Windows 10.0.26200 x64

What issue are you seeing?

In the Codex desktop app terminal/session, normal external executable invocation from PowerShell fails for multiple binaries even though the files exist on disk and are on PATH.

Observed behavior:

• git --version fails with PowerShell ResourceUnavailable / "The specified module could not be found"
• node --version fails the same way
• where.exe git also fails the same way
• Direct invocation by absolute path fails too, e.g. & 'C:\Program Files\Git\cmd\git.exe' --version

Example error shape:
Program 'git.exe' failed to run: An error occurred trying to start process 'C:\Program Files\Git\cmd\git.exe' ... The specified module could not be found.

However, the same binaries DO run successfully when launched through .NET process APIs inside the same PowerShell session, e.g. using System.Diagnostics.ProcessStartInfo with UseShellExecute = $false.

That let me run:

• C:\Program Files\Git\cmd\git.exe --version
• C:\nvm4w\nodejs\node.exe --version

So the installs themselves appear healthy; the failure seems specific to the Codex app terminal / external-process invocation path.

What steps can reproduce the bug?

1. Open the Codex desktop app on Windows.
2. Start a session in a normal repo/workspace.
3. In the PowerShell terminal, run external commands such as:

• git --version
• node --version
• & 'C:\Program Files\Git\cmd\git.exe' --version
• & 'C:\Windows\System32\where.exe' git

1. Observe that they fail with ResourceUnavailable / The specified module could not be found.
2. In the same session, run a .NET-based workaround like:

$psi = New-Object System.Diagnostics.ProcessStartInfo('C:\Program Files\Git\cmd\git.exe','--version')
$psi.UseShellExecute = $false
$psi.RedirectStandardOutput = $true
$psi.RedirectStandardError = $true
$p = New-Object System.Diagnostics.Process
$p.StartInfo = $psi
$null = $p.Start()
$p.StandardOutput.ReadToEnd()
$p.WaitForExit()

1. Observe that the process starts successfully and returns the expected output.

This suggests the binaries are valid and the problem is in the Codex app's normal terminal/process-launch path.

What is the expected behavior?

Standard PowerShell external command invocation should work normally inside the Codex desktop app terminal, including direct executable invocation by PATH or absolute path. If git.exe / node.exe / where.exe can be launched via .NET ProcessStartInfo in the same session, they should also work via normal PowerShell invocation.

Additional information

Additional notes:

• PATH looked normal and included Git, Node/NVM, Windows system directories, etc.
• The issue was broad enough to affect both third-party binaries (git.exe, node.exe) and Windows-native binaries (where.exe).
• The failure blocked normal shell-based workflows in the Codex app, including git operations, node/npm usage, and build/test commands.
• A PowerShell profile also emitted unrelated startup noise in this environment, but the executable-launch failure reproduced even when invoking binaries directly by absolute path and from a neutral working directory (C:\).
• The workaround using System.Diagnostics.ProcessStartInfo may help narrow the bug to how the app hosts or proxies terminal process creation rather than to the installed tools themselves.