Windows sandbox helper creates file but fails on subsequent read operation

Summary

The native Windows sandbox can create a temporary file successfully, but the next sandboxed read operation fails. Codex then requests permission to retry without the sandbox.

This occurs with a harmless temporary health-check file and is not related to the project code.

Environment

• Windows 10 Pro
• OS build: 19045
• Codex CLI: 0.146.0
• Model: gpt-5.6-sol
• Node.js: 24.18.0
• npm: 11.16.0
• Local trusted workspace
• Windows sandbox modes tested: elevated and unelevated

Reproduction steps

1. Open Codex CLI in a trusted local workspace.
2. Ask Codex to use the patch helper to:

• create .codex_patch_healthcheck.tmp;
• read and verify it;
• update it;
• reread it;
• delete it.

1. File creation succeeds.
2. The subsequent read operation fails.
3. Codex asks to retry without the sandbox.

Observed output

Added .codex_patch_healthcheck.tmp
Reason: command failed; retry without sandbox?
PATCH_SERVICE_UNAVAILABLE
FAILED STEP: READ