Repeated UAC prompts / ERROR_ELEVATION_REQUIRED from codex-windows-sandbox-setup.exe on Windows native sandbox

What version of the Codex App are you using (From “About Codex” dialog)?

26.602.3474.0

What subscription do you have?

Pro

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What issue are you seeing?

_I fully describe the issue I'm having below, but in the meantime, if anyone has a temporary solution to stop Windows 11 from spamming me with UAC prompts with every single thread and every message I send it, that would be a huge help. I haven't tried uninstalling Codex for Windows yet, due to fear of losing data. Thank you._

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Windows app package:
OpenAI.Codex_26.602.3474.0_x64__2p2nqsd0c76g0

Workspace is on a secondary drive:
D:\Web Development\.NET Solutions\MySolution

Codex for Windows repeatedly triggers Windows UAC prompts for:

C:\Program Files\WindowsApps\OpenAI.Codex_26.602.3474.0_x64__2p2nqsd0c76g0\app\resources\codex-windows-sandbox-setup.exe

A copied helper also exists at:

C:\Users\<redacted-user>\AppData\Local\OpenAI\Codex\bin\fb2111b91430cb17\codex-windows-sandbox-setup.exe

Both helper binaries are OpenAI-signed:

Signer: CN="OpenAI OpCo, LLC", O="OpenAI OpCo, LLC", L=San Francisco, S=California, C=US
SignatureStatus: Valid
Length: 8376112
LastWriteTimeUtc: 2026-06-04T21:44:53Z

Windows Event Viewer shows repeated UAC failures:

Log: Microsoft-Windows-UAC/Operational
Event ID: 1
Message: The process failed to handle ERROR_ELEVATION_REQUIRED during the creation of a child process.

2026-06-05 08:34:00 -05:00 ProcessId=41444
2026-06-05 08:35:03 -05:00 ProcessId=57608
2026-06-05 08:36:10 -05:00 ProcessId=63812
2026-06-05 09:14:40 -05:00 ProcessId=44004

The process ID from the latest event was gone by the time logs were inspected. The UAC event payload did not include the child executable path, but the visible UAC prompt path shown to the user was codex-windows-sandbox-setup.exe.

Current config relevant lines:

approval_policy = "on-request"
sandbox_mode = "workspace-write"

[windows]
sandbox = "elevated"

runCodexInWindowsSubsystemForLinux = false

The user reported having manually and temporarily set sandbox = "unelevated" to see if it made things more secure, but after seeing many UAC prompts appear, they manually changed it back to elevated, but the UAC prompts continued as if it didn't change back.

Runtime/UI also had “approve for me” enabled during repro. Starting Codex “as administrator” did not stop the prompts. In prior inspection, active Codex processes still appeared to run medium-integrity even when launched via Windows “Run as administrator.”

Codex app logs around the latest repro show:

2026-06-05T14:12:17.540Z method=windowsSandbox/readiness durationMs=563 errorCode=null
2026-06-05T14:14:28.565Z computer-use native pipe startup failed: Windows Computer Use helper paths are unavailable
2026-06-05T14:14:53.055Z method=turn/start

The app log does not appear to record the UAC failure directly.

What steps can reproduce the bug?

1. On Windows, set Codex config to use native Windows sandbox:

sandbox_mode = "workspace-write"

[windows]
sandbox = "elevated"

1. Enable “approve for me” in the Codex UI.
2. Start Codex for Windows.
3. Open/start multiple local threads in a workspace on D:\....
4. Codex begins showing repeated Windows UAC prompts for codex-windows-sandbox-setup.exe.
5. Windows logs Microsoft-Windows-UAC/Operational Event ID 1, ERROR_ELEVATION_REQUIRED.

What is the expected behavior?

Codex should either complete sandbox setup once, prompt once with a clear explanation, or fail once with an actionable error. It should not repeatedly trigger UAC prompts or repeatedly attempt an elevation-required child process without backoff.

Additional information

The Codex sandbox users exist and are enabled:

CodexSandboxOffline: Enabled, recent logon observed
CodexSandboxOnline: Enabled

The current tool session runs as codexsandboxoffline at medium integrity, which suggests native Windows sandboxing is active.

The main GUI executable has an embedded manifest with:

<requestedExecutionLevel level="asInvoker" uiAccess="false"/>

No requestedExecutionLevel string was found by text scan in codex-windows-sandbox-setup.exe or resources\codex.exe.