Windows sandbox helper launch fails after update: ShellExecuteExW 1223

What version of Codex CLI is running?

0.142.0-alpha.1 Codex Desktop WindowsApps package observed by doctor: OpenAI.Codex_26.616.4196.0 The issue originally started after update to: OpenAI.Codex_26.616.3767.0

What subscription do you have?

PLUS

Which model were you using?

gpt-5.4 high

What platform is your computer?

Windows 11 Professional, 10.0.26100, x64, zh-CN

What terminal emulator and version are you using (if applicable)?

Windows PowerShell 5.1 / classic PowerShell console window launched by Codex Desktop

Codex doctor report

{
  "schemaVersion": 1,
  "generatedAt": "1781885143s since unix epoch",
  "overallStatus": "fail",
  "codexVersion": "0.142.0-alpha.1",
  "notes": "Full codex doctor --json was run locally. The main failing check was terminal.env: TERM=dumb. Installation check was OK. Current WindowsApps package observed by doctor: OpenAI.Codex_26.616.4196.0. The sandbox helper issue originally started after update to OpenAI.Codex_26.616.3767.0 and is still being investigated after the later package update.",
  "keyChecks": {
    "installation": "ok - installation looks consistent",
    "auth.credentials": "ok - auth is configured",
    "network.provider_reachability": "ok",
    "network.websocket_reachability": "ok",
    "sandbox.helpers": "ok - sandbox configuration is readable; filesystem sandbox shown as unrestricted, network sandbox enabled",
    "terminal.env": "fail - TERM=dumb; expected TERM=xterm-256color or another real terminal type",
    "system.environment": "Windows 10.0.26100 / Windows 11 Professional / zh-CN",
    "runtime.provenance": "Codex CLI 0.142.0-alpha.1, windows-x86_64"
  }
}

What issue are you seeing?

Feedback thread ID: 019ee09a-d5dc-7850-bb14-0346df654d3a

After updating Codex Desktop on Windows to 26.616.3767.0, sandbox/helper launch became unstable. apply_patch can sometimes create a file, but deleting/editing later fails with:

windows sandbox failed: orchestrator_helper_launch_canceled: ShellExecuteExW failed to launch setup helper: 1223

Windows popup also shows codex-windows-sandbox-setup.exe with:
"The specified module could not be found."

The issue started immediately after the 2026-06-19 update.

What steps can reproduce the bug?

Uploaded thread: 019ee09a-d5dc-7850-bb14-0346df654d3a

What is the expected behavior?

Codex should consistently launch the Windows sandbox helper and complete file edit operations, including create, modify, and delete, without intermittent ShellExecuteExW 1223 failures.

If the helper cannot launch, the error should include the exact failing executable path and a remediation step.

Additional information

Related to #24259, but my environment is Windows 11 x64, not ARM64.

Issue started immediately after Codex Desktop updated on 2026-06-19.

Current observed versions:

• Codex CLI: 0.142.0-alpha.1
• Codex Desktop WindowsApps package: OpenAI.Codex_26.616.4196.0
• Original failing package after update: OpenAI.Codex_26.616.3767.0
• OS: Windows 11 Professional 10.0.26100 x64 zh-CN

Observed behavior:

• apply_patch can create .sandbox_probe.tmp
• deleting the same file later fails with:

windows sandbox failed: orchestrator_helper_launch_canceled: ShellExecuteExW failed to launch setup helper: 1223

• Windows popup says:

codex-windows-sandbox-setup.exe
The specified module could not be found.

Uninstalling/reinstalling Codex did not fix it.
Feedback thread ID:
019ee09a-d5dc-7850-bb14-0346df654d3a

<img width="558" height="173" alt="Image" src="https://github.com/user-attachments/assets/596625e2-73af-42a3-91b7-791c90fd9ab0" />

<img width="786" height="75" alt="Image" src="https://github.com/user-attachments/assets/e32d5662-9a02-4b26-a790-c6b0fe28c4ed" />

sandbox.2026-06-19.log