Windows Browser Use fails before opening: Node Access Denied / os error 5

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

26.430.10722

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?

Feedback ID: 019de73a-b764-7b83-95a4-85f29698aad3

I’m using Codex Desktop on Windows 11. Normal workspace/file access works, but Browser Use fails before the browser opens.

Main error:
failed to execute Node: Access is denied. (os error 5)

The failure happens before navigation, so this does not appear to be a website or network issue.

What steps can reproduce the bug?

Uploaded thread: 019de73a-b764-7b83-95a4-85f29698aad3

1. Open Codex Desktop on Windows 11.
2. Open a simple test workspace: C:\CodexTest
3. Confirm workspace access works:

• Read AGENTS.md
• List project folder
• Run pwsh

1. Ask Codex to open Browser Use and navigate to https://example.com
2. Browser does not open.
3. Codex reports: failed to execute Node: Access is denied. (os error 5)

What is the expected behavior?

Expected: Browser Use should open the in-app browser and load https://example.com.

Actual: Browser Use fails before the browser opens.

Result:

• Browser opened: no
• example.com loaded: no
• Node access denied / os error 5: yes
• Network blocked error: no

Additional information

Normal Codex functions work:

• Workspace file reads work.
• PowerShell 7 / pwsh works.
• Workspace folder listing works.
• Network access test works.
• Dependency Diagnose reports healthy.
• Reset and install Workspace eventually completed successfully.

Tried:

• Rebooted Windows.
• Closed Codex and ended all Codex background processes in Task Manager.
• Changed Windows sandbox from elevated to unelevated.
• Enabled workspace network access:

[sandbox_workspace_write]
network_access = true

• Tested with Full Access enabled: still fails.
• Tested with Full Access disabled: still fails.
• Ran Dependency Diagnose: healthy.
• Ran Reset and install Workspace: initially failed, later succeeded when running Codex as administrator, and later also succeeded normally.
• Checked Windows Security → Protection History: no recent blocks.
• Reinstalled Codex: Browser Use still fails.
• Tested clean reinstall before opening: still fails on https://example.com.

Current config highlights:
approval_policy = "on-request"
sandbox_mode = "workspace-write"

[sandbox_workspace_write]
network_access = true

[windows]
sandbox = "unelevated"