Windows sandbox setup fails validating long cua_node runtime paths

“Even a simple read-only command such as Get-Date cannot run.”

Is this your bug? What gets counted gets fixed. Pile on.

Paste this into your agent. It files your report, with your error and version.

I hit this bug: rapsheet.dev/sheets/codex/issues/14373/file
Follow it to file my report. Show me the text before you send.

No install. No account. Public and anonymous. The link asks your agent for one report, nothing else. What it sends

Quiet. No reports and thumbs-up in the last two weeks, down from 8 a week at the late-September peak. A workaround is known.

Sandboxed commands fail before the requested command starts, with the sandbox log showing runtime read/execute validation failing on a cua_node runtime directory.

Is this your bug?

File my report

Where: Windows sandbox
Error text: helper_unknown_error: setup refresh had errors
Versions: 0.155.0 to 26.930.21537
Platforms: Windows
How bad: Stops work: a core feature can't be used. Most reports say it used to work. Some reports say it blocks them completely.

Part of: Windows sandbox setup blocks commands18 bugs

Sandbox setup refresh fails308 people
Sandbox fails at deny-read ACLs10 people
Setup refresh error blocks commands23 people
Sandbox setup lock failure12 people
Split writable root sandbox failure3 people
Sandbox fails on WSL UNC paths4 people
Windows setup stops without UAC3 people
Sandbox ACL update failure2 people
Sandbox ACL refresh fails2 people
Managed networking sandbox error2 people

Show all 17Show only the largest 10

Sandbox refresh fails on old runtime2 people
Sandbox fails on Google Drive2 people
Sandbox provisioning failed2 people
Windows sandbox provisioning fails3 people
Windows sandbox setup access denied2 people
Root read access sandbox error12 people
Shell and Node tools fail with MXC 0x80070020 on Windows2 people

Original reports3, newest first

Oct 2, 2026Windows: Codex App local execution fails with “setup refresh had errors” on a long runtime pathOn GitHub#50268
Sep 18, 2026[Windows] Regression in CLI 0.155.0: elevated sandbox initialization fails during runtime path validation; 0.154.0 worksOn GitHub#46388
Sep 17, 2026Windows sandbox provisioning fails on stale CUA dependency-cache paths over 260 charactersOn GitHub#46255