Windows Store 26.707.3748.0: EFS copyfile UNKNOWN breaks bundled marketplace and Computer Use native pipe

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

26.707.3748.0

What subscription do you have?

ChatGPT Plus

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What issue are you seeing?

The Microsoft Store Codex package resources are EFS-encrypted. Codex Desktop's native copyfile operation fails with UNKNOWN / errno -4094 while relocating bundled plugins and cua_node.

Confirmed impact:

• plugin_marketplace_folder_write_failed
• bundled_plugins_marketplace_resolve_failed
• Browser is removed with reason=not_in_bundled_marketplace_plugin_names
• Computer Use reports missingHelperPath=true
• Computer Use reports missingTransportModulePath=true
• computer_use_native_pipe_thread_config_skipped reason=not-ready
• The codex-computer-use-* native pipe is not created

The existing user-side seven-plugin marketplace and the existing 3,558-file cua_node runtime are already complete, but Desktop does not reuse them after relocation fails.

A full sanitized technical report is attached.

Codex-Windows-EFS-Copyfile-Bug-Report.pdf

What steps can reproduce the bug?

1. Install or launch the Microsoft Store package OpenAI.Codex_26.707.3748.0_x64__2p2nqsd0c76g0.
2. Start Codex Desktop normally.
3. Desktop creates a new openai-bundled.staging-<GUID> directory and attempts to copy bundled resources from WindowsApps.
4. Native copyfile fails on an EFS-encrypted packaged resource with UNKNOWN / errno -4094.
5. Marketplace reconciliation runs against the failed result and may remove Browser.
6. Computer Use initialization reports missingHelperPath=true and missingTransportModulePath=true.
7. No codex-computer-use-* native pipe is created.

The same EFS-encrypted source file can be read and written successfully using byte-stream operations, while native .NET File.Copy fails with "The specified file could not be copied."

Native copying also fails when using the real package path directly, bypassing the C:\Program Files\WindowsApps junction. Therefore, the failure is not caused by the drive location or junction.

What is the expected behavior?

Codex Desktop should initialize its bundled plugins and Computer Use runtime successfully from a Microsoft Store package whose resources are EFS-protected.

On Windows, Desktop should:

1. Fall back to byte-stream copying when native copyfile fails but the source file is readable.
2. Validate and reuse an existing complete versioned runtime when relocation fails.
3. Preserve the last known-good bundled marketplace when a new staging operation fails.
4. Avoid uninstalling bundled plugins based on an incomplete or failed staging result.
5. Create the codex-computer-use-* native pipe and inject valid helper and transport paths.
6. Keep Browser, Chrome, and Computer Use available after normal Desktop restarts.

Additional information

The existing user-side fallback data is already complete:

• The bundled marketplace contains all seven current plugins: sites, browser, chrome, computer-use, latex, deep-research, and visualize.
• File-by-file comparison found no missing official plugin files.
• The existing user-side cua_node runtime contains exactly the same 3,558 files as the current Store package.
• manifest.json, node.exe, node_repl.exe, and @oai/sky/package.json have matching SHA-256 values.
• Chrome and Computer Use latest paths are native Windows NTFS junctions pointing to stable versioned cache directories.
• The Chrome native messaging manifest points to a stable versioned host executable.

Despite this, Desktop performs a new relocation and marketplace staging operation during every launch and does not reuse the verified complete existing copies after native copying fails.

Approximately 20 abandoned openai-bundled.staging-<GUID> directories remain from repeated failed synchronization attempts. They contain incomplete directory structures and no complete marketplace.

The main ChatGPT/Codex application, Store signature, sign-in, conversation history, configuration, and custom skills remain healthy. The confirmed user-visible impact is Browser removal and Computer Use native-pipe failure.

A full sanitized technical report is attached. The same report has also been escalated to an OpenAI Support specialist.

I would like to preserve the official Microsoft Store signature and normal Store updates. I do not want to decrypt or modify WindowsApps, change its ownership or ACLs, patch app.asar, or replace the Store package with a developer-signed build.

Codex-Windows-EFS-Copyfile-Bug-Report.pdf