codex - 💡(How to fix) Fix Windows Sandbox feature required but cannot be installed - Codex fails to initialize [1 participants]

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

codex-cli 0.117.0-alpha.12

What subscription do you have?

Enterprise

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What issue are you seeing?

Codex fails to send messages with error "Unable to send message - Set up Agent sandbox to continue".

The sandbox initialization hangs indefinitely when attempting to execute commands. Investigation revealed:

1. Sandbox log shows ACL helper process gets stuck: "read ACL helper already running; skipping spawn"
2. Testing codex sandbox windows echo "test" hangs indefinitely
3. Root cause: Windows Sandbox feature is not installed/enabled on the system
4. Attempted to enable Windows Sandbox via Windows Features but installation failed after 90 minutes (likely blocked by corporate IT policies)

Error from sandbox log (C:\Users\dbradt.codex.sandbox\sandbox.log):

What steps can reproduce the bug?

1. Use Windows 10 Enterprise with Windows Sandbox feature disabled/not installed
2. Install Codex/Windsurf
3. Open Codex and attempt to send any message
4. Observe "Unable to send message - Set up Agent sandbox to continue" error
5. Sandbox initialization hangs indefinitely

To verify Windows Sandbox status:

• Open "Turn Windows features on or off"
• Check if "Windows Sandbox" is unchecked
• Attempting to enable it may fail on corporate-managed systems

Configuration tested:

• config.toml with sandbox = "elevated" (with admin rights)
• config.toml with sandbox = "none" and enabled = false
• Cleared sandbox state directories (.sandbox, .sandbox-secrets, .tmp)
• Killed stuck sandbox processes
• All configurations result in same hanging behavior

Also tried to enable Windows sandbox. Machine attempted to do this update for 90 minutes and then it failed.

What is the expected behavior?

Codex should either:

1. Detect that Windows Sandbox feature is not available and provide a clear error message explaining the requirement
2. Provide alternative sandbox mechanisms (WSL, Docker, or restricted token mode) that don't require Windows Sandbox feature
3. Allow graceful degradation or fallback when Windows Sandbox is unavailable
4. Document Windows Sandbox as a system requirement in installation documentation

Expected error message example: "Windows Sandbox feature is required but not installed. Please enable it via Windows Features or contact your IT administrator."

Additional information

• System: Windows 10 Enterprise 2009 (Build 26200)
• Codex version: 0.117.0-alpha.12
• Running with Administrator privileges
• Corporate-managed system where Windows Sandbox installation is blocked by IT policy
• Virtualization appears to be available (HyperVisorPresent check passed)
• Issue affects both Windsurf-integrated Codex and standalone Codex app
• Worked once briefly, then stopped working (suggesting sandbox state corruption)

This appears to be a common issue in enterprise environments where Windows Sandbox feature cannot be enabled due to corporate security policies. A workaround or alternative sandbox mechanism would greatly improve enterprise usability.