Codex on Windows: every command fails with `helper_unknown_error: setup refresh had errors` after the October 8 update (fixed in desktop 26.1007.2314.0)

Context

Source(s): https://github.com/openai/codex/issues/52179 Status: reported working by source, not reproduced by us.

Problem

After the Codex desktop update of 2026-10-08, every sandboxed command (even a read-only Get-Location or pwd) is rejected before the shell starts. The in-app browser control and computer-use tools fail too (node_repl kernel exited unexpectedly). Restarting the app or Windows, retrying sandbox setup, and switching to the unelevated sandbox didn't help one commenter (another reported the unelevated sandbox worked while the elevated one failed).

Error (redacted / normalized)

helper_unknown_error: setup refresh had errors

exec_command failed: CreateProcess { message: "Rejected(\"Failed to create unified exec process: helper_unknown_error: setup refresh had errors\")" }

runtime read/execute validation failed: validate runtime read/execute access on <codex-runtimes>\cua_node\<runtime-id>\bin\node_repl.exe: open ACL target for root-only update: <file in use, cannot access> (os error 32)
setup refresh completed with errors: [...]
setup error: setup refresh had errors

Applies when

Windows 10 and 11, Codex desktop 26.1002.52244 (Store package 26.1002.7124.0) with bundled codex-cli 0.162.0-alpha.2, [windows] sandbox = "elevated", workspace-write permissions. A commenter saw the same error with the npm Codex CLI 0.161.0 and 0.162.1.

Confirm it is this problem

1. Open today's sandbox log (sandbox.<date>.log in the .sandbox folder under your Codex home) → expect: open ACL target for root-only update ... (os error 32) on node_repl.exe (or another file) inside the bundled cua_node runtime.
2. A command you approve to run outside the sandbox works, while every sandboxed command fails.

Not this when / boundary

helper_sandbox_lock_failed is a different sandbox error (a commenter traced it to the owner of the .sandbox-bin folder). On Windows with "Run agent in WSL", Failed to create unified exec process: No such file or directory (os error 2) is a different bug.

Root cause

According to the original poster's analysis, sandbox setup tries to update the ACL of every file in the bundled computer-use runtime, but the app's own helper processes (started about 35 seconds after launch) keep those files open, so the update fails with a sharing violation and setup fails closed, rejecting every command. (Another commenter showed the file can be opened for an ACL update outside Codex, so the exact mechanism is disputed; the fix below does not depend on it.)

Fix

1. Update the Codex desktop app to 26.1007.2314.0 or later and restart it. → expect: the original poster confirmed it is fixed on that version, back on [windows] sandbox = "elevated" with no workaround.
2. Only if you use the standalone CLI and can't move to a fixed build yet: quit the desktop app, back up config.toml in your Codex home, then comment out the whole [mcp_servers.node_repl] and [mcp_servers.node_repl.env] sections and the notify line that points at the computer-use helper, and set enabled = false for the bundled computer-use and unified-computer-use plugins. → expect: a commenter reported sandboxed commands run normally after this. The desktop app will probably re-add these entries the next time it starts (commenter).
3. Only for the npm CLI, if you can't move to a fixed build yet: a commenter pins npm i -g @openai/codex@0.160.1, which worked on the same machine where 0.161.0 to 0.162.1 failed, and runs a one-command probe before each batch. → expect: every run works on 0.160.1 (commenter). Move back to a current release once it is fixed.

How to verify

Ask Codex to run Get-Location (or pwd) with the default sandbox → expect: it prints the working directory instead of setup refresh had errors.

What did not work

Restarting Windows and the app, retrying sandbox setup, switching to the unelevated sandbox (one commenter; another said it worked), resetting the JavaScript kernel.

Risks

our note: do not work around this by giving the session full access or approving every command to run outside the sandbox; that removes the protection the sandbox exists for. Keep the config.toml backup from step 2 so you can undo it.

Verified scope

Codex desktop 26.1002.x on Windows and codex-cli 0.161.0 to 0.162.1, October 2026.

Becomes obsolete when

n/a once on desktop 26.1007.2314.0 or later; recheck if a later update brings it back.