Codex on Windows falls back to a weaker sandbox and breaks patching

felipebsr · reddit · 2026-07-23

A Windows user reports that the new ChatGPT/Codex desktop app falls back to an unelevated restricted-token sandbox.
In that state, ordinary file writes work, but applypatch fails on existing files and Node child processes fail with EPERM.
The poster includes a detailed repro: Windows build, Codex package version, sandbox user setup, and tests showing that the same project works outside the Codex sandbox.
Their theory is that the elevated sandbox runner is installed, but the runtime is incorrectly falling back to a weaker sandbox that cannot enforce split writable roots.
They ask whether others have seen the same exact error, and whether there is a supported fix, log, or Windows event that identifies the fallback cause.

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