Windows Codex app: bundled node.exe fails with Access is denied, breaking Node REPL and Browser Use plugin
Open 💬 7 comments Opened Apr 24, 2026 by debnathaniruddha89-design
💡 Likely answer: A maintainer (github-actions[bot], contributor)
responded on this thread — see the highlighted reply below.
What version of the Codex App are you using (From “About Codex” dialog)?
26.422.2339.0
What subscription do you have?
ChatGPT account, Codex desktop app on Windows
What platform is your computer?
Windows x64
What issue are you seeing?
TLDR-On Windows, Codex installs as an MSIX/Store-style app under C:\Program Files\WindowsApps. The bundled Node runtime cannot be executed, which causes node_repl and the Browser Use / in-app browser plugin to fail.
The Codex Windows app installs under:
C:\Program Files\WindowsApps\OpenAI.Codex_26.422.2339.0_x64__2p2nqsd0c76g0\app
The bundled Node runtime cannot be executed:
C:\Program Files\WindowsApps\OpenAI.Codex_26.422.2339.0_x64__2p2nqsd0c76g0\app\resources\node.exe
Running it directly from PowerShell fails with:
Program 'node.exe' failed to run: Access is denied
The Node REPL also fails with:
failed to execute Node: Access is denied. (os error 5)
This breaks the Browser Use / in-app browser plugin, because it depends on the Node REPL runtime.
What steps can reproduce the bug?
- Install Codex on Windows.
- Open a Codex thread.
- Try to use Browser Use / in-app browser automation, or run Node REPL.
- It fails with
Access is denied.
Direct PowerShell test:
& 'C:\Program Files\WindowsApps\OpenAI.Codex_26.422.2339.0_x64__2p2nqsd0c76g0\app\resources\node.exe' --version
Output-Program 'node.exe' failed to run: Access is denied
### What is the expected behavior?
Codex’s bundled node.exe should execute successfully, allowing node_repl and Browser Use / in-app browser automation to work.
### Additional information
Troubleshooting tried
Uninstalled McAfee
Ransomware protection page became accessible afterward
Reinstalled Codex
Tried launching Codex as administrator
Tried giving Codex full permissions
Verified Browser Use plugin file exists:
C:\Users\Aniruddha Debnath.codex\plugins\cache\openai-bundled\browser-use\0.1.0-alpha1\scripts\browser-client.mjs
Active Codex process still runs from WindowsApps
Bundled node.exe remains blocked with Access is denied
Edit: for the codex team, this is how 5.5 xhigh diagnosed the situation, i am a nontechnical user, i have zero idea about how all of this works--
Copy-paste this into the GitHub issue:
### Summary
On Windows, Codex’s in-app browser / Browser Use runtime failed with:
```text
failed to execute Node: Access is denied. (os error 5)
This was reproducible even with a minimal Node REPL call, so the issue is not specific to Browser Use navigation.
Environment
OS: Windows
Codex app install path involved:
C:\Program Files\WindowsApps\OpenAI.Codex_26.422.2437.0_x64__2p2nqsd0c76g0\app\resources
Affected packaged helpers:
node.exe
rg.exe
What failed
node resolved to:
C:\Program Files\WindowsApps\OpenAI.Codex_26.422.2437.0_x64__2p2nqsd0c76g0\app\resources\node.exe
Running:
node --version
failed with:
Program 'node.exe' failed to run: Access is denied
The Node REPL MCP also failed with:
failed to execute Node: Access is denied. (os error 5)
rg.exe from the same app resources directory showed the same access-denied behavior.
What worked
The user-cache Codex runtime copy of Node worked:
C:\Users\Aniruddha Debnath\.cache\codex-runtimes\codex-primary-runtime\dependencies\node\bin\node.exe
Running that directly returned:
v24.14.0
Copying the working node.exe and rg.exe into the earlier per-session PATH directory:
C:\Users\Aniruddha Debnath\.codex\tmp\arg0\codex-arg0ZQRaO8\
made these commands work again:
node --version
rg --version
After that, the Node REPL MCP worked and the in-app browser opened successfully.
Suspected root cause
Codex is resolving helper binaries from the protected WindowsApps package directory. In this environment, Windows denies execution of those packaged helper binaries from spawned tool/MCP contexts.
Suggested fix
Please avoid resolving helper binaries like node.exe / rg.exe from the protected WindowsApps app resources path when spawning Codex tool runtimes.
Prefer an unpacked per-user executable runtime path, for example:
%USERPROFILE%\.cache\codex-runtimes\codex-primary-runtime\dependencies\node\bin\node.exe
Or copy/unpack helper executables into a per-user/per-session executable cache and prepend that directory to PATH before starting MCP/tool subprocesses.
The workaround confirms the browser runtime itself is fine once Node can execute. The permanent fix should be in Codex’s helper binary resolution / PATH setup on Windows, not in Browser Use itself.
This should give maintainers the important bits: exact error, exact bad path, exact working path, workaround, and the likely product-side fix.
7 Comments
Potential duplicates detected. Please review them and close your issue if it is a duplicate.
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Same issue here on Windows.
Environment:
What works:
What fails:
Browser Use error:
failed to start codex app-server: The system cannot find the path specified. (os error 3)
Local runtime check:
This looks like the same Windows/MSIX bundled runtime issue, with Browser Use failing downstream because app-server / Node REPL cannot start.
hello, can the codex app access the node REPL backend from your system? i am getting an os error 5 from my system
<img width="960" height="232" alt="Image" src="https://github.com/user-attachments/assets/94686760-421f-49fa-b0c3-29c9fa6f2306" />
for the codex team, if anyone is reading this, this is how 5.5 xhigh diagnosed the situation
Copy-paste this into the GitHub issue:
Summary
On Windows, Codex’s in-app browser / Browser Use runtime failed with:
I was able to reproduce and work around this on Windows with Codex 26.422.3464.0.
The failure was not Browser Use itself. Browser Use initialized and could see the IAB tab, but external navigation failed because nodeRepl.fetch could not start/use the Codex app-server.
Root cause in my environment:
Codex helpers existed under the MSIX LocalCache path:
%LOCALAPPDATA%\Packages\OpenAI.Codex_2p2nqsd0c76g0\LocalCache\Local\OpenAI\Codex\bin
but Node REPL / spawned helper paths referred to:
%LOCALAPPDATA%\OpenAI\Codex\bin
That non-MSIX path did not exist, so nodeRepl.fetch failed with:
failed to start codex app-server: The system cannot find the path specified. (os error 3)
Workaround:
Create %LOCALAPPDATA%\OpenAI\Codex\bin and copy the helper binaries from the MSIX LocalCache bin folder:
codex.exe, node.exe, node_repl.exe, rg.exe, codex-command-runner.exe, codex-windows-sandbox-setup.exe.
After that:
nodeRepl.fetch(...) returned 200
Browser Use tab.goto("https://example.com/") worked
domSnapshot and screenshot worked
Suggested product fix:
On Windows/MSIX builds, ensure tool/MCP/runtime helper resolution uses a real per-user executable path, or creates/syncs %LOCALAPPDATA%\OpenAI\Codex\bin before starting node_repl/app-server. Avoid resolving helpers from WindowsApps or from a path that only exists inside MSIX package virtualization.
@vadimsky-ctrl
Thank you very much for posting your workaround. I’ve just implemented it and it works wonderfully, especially browser use and rg.exe.
I was already extremely desperate because I had the impression that almost nothing worked properly with the Codex app under Windows. Even my sandbox isn’t really functioning, and I have already once destroyed my entire C: drive with this app. :-((( Fortunately, I make daily backups, so it wasn’t too bad.
Your workaround is excellent because now I can work much more productively. I’ve spent the last few weeks just programming my own skills and workarounds and tool outsourcing to avoid these errors. But now I can finally work with the Codex app exactly as it should be. I hope that OpenAI will quickly resolve these and similar issues, and I honestly wonder if they even have a test department because such things should stand out immediately when testing the basic functions of a new Codex app version.
Well, whatever... with your workaround, I can now finally work with this app, and I sincerely hope that OpenAI employees read this thread here and hopefully also take it seriously. Thank you very much, and all the best.
Small update from #20747 (my original Windows 11 Browser Use issue with: failed to execute Node: Access is denied. (os error 5))
is no longer reproducible on my machine, so I closed my issue.
I’m not sure whether it was fixed by a Codex update, a Windows update/reboot, or some local state change. Browser Use in Codex Desktop is now working for me.
Separate note: I first noticed that the Browser Use started working while testing the new Codex Chrome plugin, but I’m still having some separate issues with the Chrome plugin itself saying "I don’t have the Chrome plugin available in this session, so I can’t directly control a browser window."