Codex Desktop Windows: node_repl fails with "windows sandbox failed: spawn setup refresh", breaking Chrome plugin

Resolved 💬 9 comments Opened May 28, 2026 by jorgeperaltanavarro-coder Closed Jun 12, 2026

💡 Likely answer: A maintainer (iceweasel-oai, contributor) responded on this thread — see the highlighted reply below.

Bug report: Codex Desktop on Windows cannot start node_repl sandbox, breaking Chrome plugin

Summary

Codex Desktop on Windows can no longer use the Chrome plugin or any node_repl-backed browser automation. The failure occurs before Chrome is used: even a minimal node_repl call exits immediately with:

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 previously worked on the same machine.

Environment

OS: Windows Desktop v10.0.26200.8457
Codex Desktop package: OpenAI.Codex_26.519.11010.0_x64__2p2nqsd0c76g0
Codex app version shown by winget/MS Store: 26.519.11010.0
Winget version: v1.28.240
Chrome plugin cache version regenerated after cleanup: 26.519.81530
Chrome native host extension ID: hehggadaopoacecdllhhajmbjkdcmajg

What fails

Any call to the node_repl MCP tool fails, including the minimal test:

nodeRepl.write("ok")

Observed result:

node_repl kernel exited unexpectedly
node_repl diagnostics: {"kernel_pid":9592,"kernel_status":"running","kernel_stderr_tail":"windows sandbox failed: spawn setup refresh","reason":"stdout_eof","stream_error":null}

Because node_repl fails, the Chrome plugin cannot connect to or automate Chrome.

Things already verified

Chrome/plugin side appears healthy after reset:

Chrome plugin cache regenerated under:

C:\Users\Jorge\.codex\plugins\cache\openai-bundled\chrome

Native host manifest exists:

C:\Users\Jorge\AppData\Local\OpenAI\extension\com.openai.codexextension.json

Native messaging registry key exists:

HKCU\Software\Google\Chrome\NativeMessagingHosts\com.openai.codexextension

Registry value points to:

C:\Users\Jorge\AppData\Local\OpenAI\extension\com.openai.codexextension.json

So the remaining issue is not the Chrome extension or native host registration; it is node_repl failing to start its Windows sandbox kernel.

Repair attempts performed

Reinstalled the Chrome plugin from Codex UI.
Removed/regenerated Chrome plugin cache:

C:\Users\Jorge\.codex\plugins\cache\openai-bundled\chrome

Removed/regenerated native host manifest:

C:\Users\Jorge\AppData\Local\OpenAI\extension

Removed/regenerated native messaging registry key:

HKCU\Software\Google\Chrome\NativeMessagingHosts\com.openai.codexextension

Ran winget upgrade for Codex:

result: no newer version available.

Ran winget repair for Codex from Microsoft Store.
Re-registered the Codex AppX package with:

Add-AppxPackage -DisableDevelopmentMode -Register "C:\Program Files\WindowsApps\OpenAI.Codex_26.519.11010.0_x64__2p2nqsd0c76g0\AppxManifest.xml"

The AppX re-registration completed successfully, but node_repl still fails with the same sandbox error.

Relevant logs/results

Successful AppX repair log:

[2026-05-28 15:52:02] Running Add-AppxPackage repair.
[2026-05-28 15:52:02] Repair completed successfully.
[2026-05-28 15:52:02] Relaunching Codex.
[2026-05-28 15:52:02] Codex relaunch requested.

Repeated failing test after repair:

node_repl kernel exited unexpectedly
node_repl diagnostics: {"kernel_pid":9592,"kernel_status":"running","kernel_stderr_tail":"windows sandbox failed: spawn setup refresh","reason":"stdout_eof","stream_error":null}

Expected behavior

node_repl should start its kernel successfully, and the Chrome plugin should be able to list/control Chrome tabs as it did previously.

Actual behavior

node_repl fails before executing any JavaScript, with windows sandbox failed: spawn setup refresh.

Impact

This blocks all Chrome plugin workflows from Codex Desktop, including authenticated browser automation through the user's existing Chrome session.

Request

Please investigate the Windows sandbox startup path for node_repl in Codex Desktop 26.519.11010.0, especially the spawn setup refresh step. If there is a supported repair command, cache reset, feature flag, or diagnostic bundle needed, please provide the exact steps.

View original on GitHub ↗

9 Comments

jorgeperaltanavarro-coder · 1 month ago

Adding a potentially related issue for triage: #24259.

That report is for Codex CLI on Windows 11 ARM64, while this one is Codex Desktop on Windows x64/MS Store. The surface area is different, but the failing component/error string looks related:

windows sandbox failed: spawn setup refresh

In #24259, sandboxed CLI commands intermittently fail with windows sandbox: spawn setup refresh. In this issue, node_repl fails consistently before executing even a minimal JS call, which then breaks the Chrome plugin because browser automation depends on node_repl.

So this may be the same Windows sandbox helper/startup failure family, but surfaced through Codex Desktop's node_repl path rather than direct CLI shell execution.

jorgeperaltanavarro-coder · 1 month ago

Also adding #24098 as an even closer related report.

That issue is still Codex CLI rather than Codex Desktop, but it is Windows x64 and has the same core failure string:

windows sandbox failed: spawn setup refresh

The especially useful clue from #24098 is that the elevated Windows sandbox fails while the unelevated Windows sandbox succeeds. In this Desktop issue, node_repl fails before any JS executes, so one possibility is that the Desktop node_repl startup path is using the same elevated Windows sandbox path, or another sandbox mode that hits the same spawn setup refresh failure.

This may help narrow the bug: Chrome/native-host registration appears healthy here, and the failure happens at node_repl kernel startup, before Chrome automation is attempted.

carypdarling-star · 1 month ago

I’m seeing the same issue on Windows Codex Desktop.

Minimal node_repl test fails before any Browser Bridge code runs:

nodeRepl.write("ok")

Result:

node_repl kernel exited unexpectedly
node_repl diagnostics: {"kernel_pid":16332,"kernel_status":"running","kernel_stderr_tail":"windows sandbox failed: spawn setup refresh","reason":"stdout_eof","stream_error":null}

This also prevents Browser Bridge / Chrome tab control from working.

IDK-CCC · 1 month ago

C:\Users\admin\.codex\config.toml ：
[windows]
sandbox = "elevated"
change
sandbox = "unelevated"

carypdarling-star · 1 month ago

Changing my Codex user config from:

[windows]
sandbox = "elevated"

to:

[windows]
sandbox = "unelevated"

fixed the node_repl startup crash for me. Minimal test nodeRepl.write("ok") now succeeds.

cyberpunx777 · 1 month ago

I’m seeing this too on Windows with Codex Desktop / bundled plugins 26.527.60818.

node_repl was crashing with:

windows sandbox failed: spawn setup refresh

That also broke Chrome plugin control for me. Switching:

[windows]
sandbox = "elevated"

to:

[windows]
sandbox = "unelevated"

made node_repl and Chrome control work again.

So this may be tied to the elevated Windows sandbox path. Would really appreciate a fix or guidance from the team, since unelevated feels like a workaround rather than the right long-term state.

cedric-albeke · 1 month ago

Adding a related workaround for users whose main problem is Desktop stability/performance rather than needing browser automation immediately.

Environment where this helped:

Windows 11 Pro
Store package: OpenAI.Codex_26.527.7698.0_x64__2p2nqsd0c76g0
node_repl.exe under %LOCALAPPDATA%\OpenAI\Codex\bin\34ab3e1324cc55b5\node_repl.exe

On this machine, node_repl was not only breaking browser/computer-use behavior; it also correlated with severe Desktop instability:

frozen chats
new chats sometimes not being creatable
repeated Desktop restarts not fully recovering the state
extra node_repl.exe processes, each spawning a child codex.exe app-server --listen stdio://

Setting browser plugin config off was not enough by itself. After restart, node_repl still spawned and an explicit [mcp_servers.node_repl] enabled = false entry was removed/ignored.

Workaround if browser/computer-use automation is not needed:

Disable the bundled browser plugin:

[plugins."browser@openai-bundled"]
enabled = false

Stop running node_repl.exe and its direct child codex.exe app-server --listen stdio://.

Reversibly rename local node_repl.exe binaries, e.g.:

%LOCALAPPDATA%\OpenAI\Codex\bin\<hash>\node_repl.exe -> node_repl.exe.disabled-YYYYMMDD-HHMMSS
%LOCALAPPDATA%\OpenAI\Codex\bin\node_repl.exe -> node_repl.exe.disabled-YYYYMMDD-HHMMSS

After doing this, no new node_repl.exe process was running, normal Codex chat/task execution continued, and Desktop became dramatically more stable/faster. Tradeoff: internal browser/computer-use automation is disabled until the binaries are restored or Codex updates them again.

This is not a proper fix, but it may help people who are currently unable to use Codex Desktop at all due to the node_repl path.

jorgeperaltanavarro-coder · 1 month ago

Update: confirmed workaround on my machine.

Changing my Codex user config from:

[windows]
sandbox = "elevated"

to:

[windows]
sandbox = "unelevated"

fixed the issue locally.

After applying the change:

Minimal nodeRepl.write("ok") succeeds.
Chrome plugin / Browser Bridge works again.
I can list and control Chrome tabs from Codex Desktop.

So this appears tied specifically to the elevated Windows sandbox path. unelevated is a working workaround for now, but I would still appreciate guidance from the team on whether this is the recommended temporary setting or whether a fix is planned for the elevated path.

Thanks a lot to @IDK-CCC, @carypdarling-star, and @cyberpunx777 for confirming the same behavior and pointing to the unelevated workaround. That helped resolve the blockage on my side.

iceweasel-oai contributor · 1 month ago

this is now fixed