Codex Desktop Windows: node_repl bridge fails with `windows sandbox failed: spawn setup refresh`
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\binto force helper-cache regeneration. - Verified helper cache was regenerated with hash directories including:
34ab3e1324cc55b5\node_repl.exe5b9024f90663758b\node.exe7dea4a003bc76627\codex.exe- Tried adding
args = ["--disable-sandbox"]under[mcp_servers.node_repl]; Codex launchednode_repl.exewithout passing the arg. - Tried a reversible wrapper that launched
node_repl.exe --disable-sandbox; wrapper launched correctly, but child still routed throughCODEX_CLI_PATHand failed. - Tried removing
CODEX_CLI_PATHfrom[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.
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