Codex Desktop Windows: node_repl bridge fails with `windows sandbox failed: spawn setup refresh`

Open 💬 4 comments Opened May 30, 2026 by RusBus09
💡 Likely answer: A maintainer (github-actions[bot], contributor) responded on this thread — see the highlighted reply below.

Bug Report

Codex Desktop on Windows cannot start the node_repl MCP bridge. This blocks Browser and Computer Use because even a minimal node_repl smoke test exits before running any JavaScript.

Environment

  • App: Codex Desktop for Windows / Microsoft Store package
  • Package: OpenAI.Codex_26.527.3686.0_x64__2p2nqsd0c76g0
  • Codex CLI helper observed: codex-cli 0.135.0-alpha.1
  • OS: Windows
  • Affected MCP server: node_repl
  • Affected features: Browser plugin / Computer Use plugin

Symptom

Any node_repl call fails immediately:

node_repl kernel exited unexpectedly
node_repl diagnostics: {"kernel_status":"running","kernel_stderr_tail":"windows sandbox failed: spawn setup refresh","reason":"stdout_eof","stream_error":null}

This happens even for a no-op smoke test such as:

nodeRepl.write(JSON.stringify({ ok: true, cwd: nodeRepl.cwd }, null, 2));

Because node_repl never starts, Browser and Computer Use cannot connect.

Relevant config/process evidence

%USERPROFILE%\.codex\config.toml is regenerated with:

[mcp_servers.node_repl]
args = []
command = '%LOCALAPPDATA%\OpenAI\Codex\bin\34ab3e1324cc55b5\node_repl.exe'
startup_timeout_sec = 120

[mcp_servers.node_repl.env]
NODE_REPL_NODE_PATH = '%LOCALAPPDATA%\OpenAI\Codex\bin\5b9024f90663758b\node.exe'
CODEX_CLI_PATH = '%LOCALAPPDATA%\OpenAI\Codex\bin\7dea4a003bc76627\codex.exe'

Process inspection during failure shows:

node_repl.exe
  "%LOCALAPPDATA%\OpenAI\Codex\bin\34ab3e1324cc55b5\node_repl.exe"

codex.exe child
  "%LOCALAPPDATA%\OpenAI\Codex\bin\7dea4a003bc76627\codex.exe" app-server --listen stdio://

Sandbox logs show repeated setup refresh attempts via the WindowsApps package resources path:

setup refresh: spawning C:\Program Files\WindowsApps\OpenAI.Codex_26.527.3686.0_x64__2p2nqsd0c76g0\app\resources\codex-windows-sandbox-setup.exe
setup refresh: processed 2 write roots (read roots delegated); errors=[]
setup binary completed

Despite the setup binary logging success in ordinary shell/sandbox operations, node_repl still fails with windows sandbox failed: spawn setup refresh and exits before accepting JS.

Things tried

  • Restarted Codex Desktop.
  • Logged out/in of Windows session.
  • Rebooted the PC.
  • Full uninstall/reinstall of Codex Desktop via Microsoft Store / winget.
  • Renamed %LOCALAPPDATA%\OpenAI\Codex\bin to force helper-cache regeneration.
  • Verified helper cache was regenerated with hash directories including:
  • 34ab3e1324cc55b5\node_repl.exe
  • 5b9024f90663758b\node.exe
  • 7dea4a003bc76627\codex.exe
  • Tried adding args = ["--disable-sandbox"] under [mcp_servers.node_repl]; Codex launched node_repl.exe without passing the arg.
  • Tried a reversible wrapper that launched node_repl.exe --disable-sandbox; wrapper launched correctly, but child still routed through CODEX_CLI_PATH and failed.
  • Tried removing CODEX_CLI_PATH from [mcp_servers.node_repl.env]; Codex regenerated it on restart.

Expected behavior

A basic node_repl smoke test should start the kernel and return output. Browser and Computer Use should then be able to bootstrap from node_repl.

Actual behavior

node_repl exits before running any JS, with windows sandbox failed: spawn setup refresh. Browser and Computer Use are unusable on this machine.

Impact

This blocks Codex Desktop features that depend on node_repl, including Browser and Computer Use, despite the plugins and helper binaries being present.

View original on GitHub ↗

4 Comments

github-actions[bot] contributor · 3 months ago

Potential duplicates detected. Please review them and close your issue if it is a duplicate.

  • #25222
  • #25102
  • #25090
  • #25012
  • #24963

Powered by Codex Action

Onlydreams · 2 months ago

Additional data point from another Windows Home machine:

  • OS: Windows 11 Home China, build 26200
  • Codex Desktop Computer Use fails before listing apps.
  • node_repl exits with:
node_repl kernel exited unexpectedly
node_repl diagnostics: {"kernel_status":"running","kernel_stderr_tail":"windows sandbox failed: spawn setup refresh","reason":"stdout_eof"}
  • systeminfo reports a hypervisor is detected and VBS is running.
  • Windows Sandbox feature is not present on this image:
dism /online /Get-FeatureInfo /FeatureName:Containers-DisposableClientVM

returns:

Error: 0x800f080c
Feature name Containers-DisposableClientVM is unknown.

This suggests the Desktop app should either support Windows Home through a non-Windows-Sandbox fallback path, or detect missing Windows Sandbox support and show a clear actionable error instead of crashing node_repl. Upgrading to Windows Pro would be a workaround, but it should not be the expected path for using Computer Use on Windows Home.

eliotcougar · 2 months ago

After updating Codex-CLI to 0.137.0, the npm helper contains asInvoker; Simply asking Codex App to use the Codex-CLI's codex-windows-sandbox-setup.exe helper made sky.list_apps() and Computer Use work with elevated sandbox.
I guess, the issue is fixed in CLI, but not in the Windows App, as the bundled helper doesn't yet have asInvoker flag.

kuajingquanqiu · 1 day ago

I can reproduce this issue on a newer Codex Desktop build.

Environment:

  • Codex desktop package: OpenAI.Codex
  • Codex desktop version: 26.820.7780.0
  • Executable product version: 151.0.7922.170
  • Operating system: Windows 11 Pro
  • Windows version/build: 10.0.26200 / Build 26200

Exact error:

windows sandbox failed: helper_unknown_error: setup refresh had errors

The Browser/Chrome runtime fails before opening any local page, and the runtime kernel exits unexpectedly.

This blocks built-in Browser/Chrome UAT for a local page on 127.0.0.1.

Troubleshooting already completed:

  1. Restarted Codex Desktop.
  2. Fully restarted Windows.
  3. Confirmed the app is updated.
  4. Reopened the same task.
  5. Retried the minimum Browser/Chrome health check.

Device management diagnostics:

  • PartOfDomain: False
  • AzureAdJoined: NO
  • DomainJoined: NO
  • WorkplaceJoined: NO

This is my personal computer and is not managed by corporate MDM or Group Policy.

I also checked the documented sandbox log location:

%USERPROFILE%\.codex\.sandbox\sandbox.log

Result:

LOG_NOT_FOUND

I did not access or include anything from .sandbox-secrets.

OpenAI support recommended collecting sandbox.log and testing elevated or unelevated sandbox modes. Please advise whether this issue has a supported repair procedure, fixed build, or approved workaround for Codex Desktop.