Codex Desktop Windows: stdout capture broken and node_repl elevation failure for non-Administrator user accounts

Codex Desktop Windows: stdout capture broken and node_repl elevation failure for non-Administrator user accounts

Filed by: Kyle (ToastNightmare on GitHub)
Date prepared: 2026-06-03 00:18 GMT+8 (Australia/Perth)
Codex version tested: OpenAI.Codex 26.527.7698.0 x64 (Microsoft Store)
Status: Reproducible after clean reinstall

---

Summary

Codex Desktop on Windows cannot reliably capture shell command output for users whose Windows account is not in the local Administrators group. Two distinct failure modes are present even after a clean Microsoft Store reinstall:

1. Stdout capture failure: Shell commands run via the sandbox-managed command-runner complete with exit code 0 and SUCCESS: in sandbox.log, but no output is returned to the chat UI.
2. node_repl elevation failure: The node_repl MCP server attempts to spawn C:\Users\<user>\AppData\Local\OpenAI\Codex\bin\<hash>\codex-windows-sandbox-setup.exe, which requires elevation and fails with Windows error 740 (ERROR_ELEVATION_REQUIRED) for non-admin users.

This makes Codex Desktop unusable for production coding work for users following Windows security best-practice (running as standard user).

---

Environment

• OS: Windows 11, build 10.0.26200.8524
• Codex Desktop: OpenAI.Codex 26.527.7698.0 x64 (Microsoft Store)
• User account: Standard user (whoami /groups shows NOT a member of BUILTIN\Administrators)
• PowerShell: 5.1.26100 (system), 7.6.1 (Codex-bundled pwsh)
• Node: 24.14.0 system; 22.x bundled by Codex
• Git: 2.53.0.windows.1
• pnpm: 10.33.3 (via Codex wrapper)
• Config: [windows] sandbox = "elevated" (default after install)
• Reinstall fully performed: yes, from Microsoft Store, version bumped from 26.527.3686.0 to 26.527.7698.0
• .codex/ data: preserved (not wiped)

---

Reproduction

1. Sign into a Windows account that is NOT in the local Administrators group.
2. Install Codex Desktop from the Microsoft Store.
3. Open a fresh chat with a new worktree.
4. Run any shell command, e.g.:

``
pwd
git rev-parse --show-toplevel
git branch --show-current
git status --short
node -e "console.log('node-ok')"
cmd.exe /d /c "echo cmd-ok"
powershell -NoProfile -Command "Write-Output powershell-ok"
``

---

Expected

• Each command returns its stdout in the chat UI.
• Tools that depend on subprocess output (file inspection, build verification, test runs, git status checks) work as documented.

---

Actual

Sandbox pipeline succeeds, output still missing

From C:\Users\<user>\.codex\.sandbox\sandbox.2026-06-02.log (timestamps GMT+8):

[2026-06-03 00:11:55.979] START: pwsh.cmd -NoProfile -Command try { ... } catch {}
[2026-06-03 00:11:56.068] setup refresh: spawning C:\Program Files\WindowsApps\OpenAI.Codex_26.527.7698.0_..\app\resources\codex-windows-sandbox-setup.exe
[2026-06-02T16:11:56.100] granting write ACE to C:\Users\Admin\.codex\worktrees\ed5c\app for sandbox group
[2026-06-02T16:11:56.106] read-acl-only mode: applying read ACLs
[2026-06-02T16:11:56.109] granting read ACE to C:\Users\Admin\AppData for sandbox users
[2026-06-02T16:12:06.721] applied deny ACE to protect C:\Users\Admin\.codex\worktrees\ed5c\app\.git
[2026-06-02T16:12:06.724] setup refresh: processed 2 write roots (read roots delegated); errors=[]
[2026-06-03 00:12:06.739] helper copy: validating command-runner
[2026-06-03 00:12:06.742] helper launch resolution: using copied command-runner path C:\Users\Admin\.codex\.sandbox-bin\codex-command-runner-0.136.0-alpha.2.exe
[2026-06-03 00:12:07.038] junction: created C:\Users\CodexSandboxOffline\.codex\.sandbox\cwd\55d0b68618c1c406 -> C:\Users\Admin\.codex\worktrees\ed5c\app
[2026-06-03 00:12:07.325] SUCCESS: pwsh.cmd ...

Sandbox bootstrap completes cleanly. Command-runner v0.136.0-alpha.2 is invoked. Write ACEs are granted. Junction is created. SUCCESS: is logged with exit code 0. The chat UI shows blank output.

node_repl path still fails with elevation error

[2026-06-03 00:13:03.089] START: ...AppData\Local\OpenAI\Codex\bin\5b9024f90663758b\node.exe ... kernel.js --session-id ...
[2026-06-03 00:13:03.143] setup refresh: spawning C:\Users\Admin\AppData\Local\OpenAI\Codex\bin\716dda49c14d31a0\codex-windows-sandbox-setup.exe (cwd=C:\Users\Admin\.codex\worktrees\ed5c\app)
[2026-06-03 00:13:03.310] setup refresh: failed to spawn ...: The requested operation requires elevation. (os error 740)
[2026-06-03 00:13:27.453] START: ...same node.exe...
[2026-06-03 00:13:27.508] setup refresh: failed to spawn ...: requires elevation. (os error 740)

The AppData copy of codex-windows-sandbox-setup.exe has a manifest that requires Administrator elevation. UAC prompt does not appear (none can satisfy it without admin password the user does not have). CreateProcess returns ERROR_ELEVATION_REQUIRED. Reinstall renamed the hash subdir but did not change the manifest.

---

Workarounds attempted (all unsuccessful)

• Restart Codex app (force-kill all 13-22 codex processes and relaunch)
• Backup + remove empty setup_marker.json (Codex regenerated but still with empty read_roots/write_roots in the marker file, despite runtime logs showing roots ARE being applied)
• Rename codex-windows-sandbox-setup.exe aside (Codex restored on next launch)
• Comment out [windows] section in config.toml (Codex disabled the entire sandbox-init code path, broke output capture differently)
• [windows] sandbox = "default" -- rejected: unknown variant 'default', expected 'elevated' or 'unelevated'
• [windows] sandbox = "unelevated" -- Codex accepts, skips sandbox bootstrap entirely, output capture remains blank
• Microsoft Store reinstall (version bump 26.527.3686.0 to 26.527.7698.0) -- bootstrap now works clean, output capture still broken

---

Other observations

• Dual install pattern persists across reinstall: both C:\Program Files\WindowsApps\OpenAI.Codex_...\ and C:\Users\<user>\AppData\Local\OpenAI\Codex\bin\ are populated with codex.exe, codex-windows-sandbox-setup.exe, codex-command-runner.exe, plus older orphan hash subdirs from prior versions.
• setup_marker.json reports read_roots: [], write_roots: [] even when runtime logs show 2 write roots were applied -- the marker file appears informational, not authoritative.
• Stale codex-command-runner-*.exe binaries accumulate in C:\Users\<user>\.codex\.sandbox-bin\ (currently 7 different versions from 0.126 through 0.136-alpha.2).

---

Requested fix

Either:

1. Provide a sandbox mode that produces working command-runner stdout capture without requiring Administrators-group membership, OR
2. Fix sandbox = "unelevated" to retain the command-runner IPC bridge, OR
3. Update codex-windows-sandbox-setup.exe so its AppData copy does not require elevation when invoked from a non-admin token, OR
4. Document the Administrators-group requirement clearly in install / first-run UI so users can self-diagnose.

---

Logs available on request

• C:\Users\Admin\.codex\.sandbox\sandbox.2026-06-02.log (63KB, contains the full repro window 00:00 to 00:14)
• C:\Users\Admin\.codex\config.toml (current state, default sandbox = "elevated")
• C:\Users\Admin\.codex\.sandbox\setup_marker.json (regenerated but empty roots in file)

A local copy of the sandbox log used to prepare this report is preserved and can be shared on request (it contains no credentials, just sandbox/spawn telemetry).

---

Possibly related issues filed today

• #25876 - Windows sandbox fails with standalone CLI despite valid junction install layout (same os error 740 + spawn setup refresh, CLI angle vs this report's desktop-app angle)
• #25877 - codex crashed itself and wsl2
• #25878 - Bundled plugins (chrome, browser, computer-use) become unavailable after Microsoft Store auto-update

Filing separately because the stdout capture failure under sandbox = "unelevated" and after a healthy bootstrap with sandbox = "elevated" is a distinct symptom from the above. Happy to merge / close as duplicate if maintainers determine it overlaps.