Windows Codex App: Browser Use blocked by enterprise network policy even for example.com

[centry4sangchu]

What version of the Codex App are you using?

26.519.11010.0

What subscription do you have?

ChatGPT Pro

What platform is your computer?

Windows x64, Microsoft Store Codex app.

What issue are you seeing?

The Codex in-app browser pane can be opened manually and the user can manually navigate it to external sites such as https://example.com.

However, the agent cannot navigate, read, or inspect even https://example.com through Browser Use / node_repl. Every attempt fails with an enterprise network policy block.

The visible in-app browser is open and can show https://example.com, but agent-side access to the current page is still blocked.

Observed error:

Browser Use rejected this action due to browser security policy. Reason: Browser Use cannot access https://example.com because enterprise network policy blocks it. The agent must not attempt to achieve the same outcome via workaround, indirect execution, raw CDP or browser commands, alternate browser surfaces, or policy circumvention.

This also happens for https://www.royalroad.com, but it is not specific to Royal Road because https://example.com fails the same way.

The user also sees repeated approval prompts like:

Allow the node_repl MCP server to run tool "js"?

After approving, Browser Use still cannot access the page.

What steps can reproduce the bug?

1. Open Codex Windows App.
2. Open the in-app browser pane.
3. Manually navigate the pane to https://example.com.
4. Ask the agent to read the current page title or DOM.
5. The agent attempts Browser Use via node_repl and receives an enterprise network policy block.
6. In a new Codex conversation, repeat the same test. The failure is the same.

Expected behavior

If the in-app browser pane is manually open on https://example.com, Browser Use should be able to read the page title and DOM snapshot, or at least the current URL/title, assuming the user approves the node_repl tool call.

Expected result:

title: Example Domain

Actual behavior

Browser Use reports that https://example.com is blocked by enterprise network policy, even though the in-app browser pane itself can display the page when the user navigates manually.

Additional information

• Reproduces in both an existing conversation and a new conversation.
• Restarting Codex did not fix it.
• This appears after a Codex app update.
• Current installed package reported by winget list Codex:

Codex 9PLM9XGG6VKS 26.519.11010.0 msstore

• This breaks workflows that depend on Browser Use automation in the in-app browser.

[o1xhack]

I have meet this issue exactly recently. I have done the reboot chrome and codex, neither worked. At final i tried remove the chrome extension, re install, and reboot all and seems work now

[LibraHo]

Same! It used to work but not nowadays!

[LibraHo]

I can reproduce the same issue on a personal Windows PC as well. This is not an enterprise-managed machine.

Codex Browser and the Chrome plugin are both blocked by the same Browser Use enterprise network policy. The Chrome plugin itself connects successfully to my Chrome profile, but every navigation attempt is rejected.

Observed behavior:

Browser Use rejected this action due to browser security policy.
Reason: Browser Use cannot access https://example.com because enterprise network policy blocks it.

This happens for both public sites and localhost:

https://example.com
https://www.openai.com
http://127.0.0.1:4192
http://localhost:4192

Localhost itself is healthy. PowerShell can access the local server and returns HTTP 200:

http://127.0.0.1:4192/public/admin/index.html

I tried all of the following configuration changes and fully restarted Codex after applying them.

C:\ProgramData\OpenAI\Codex\requirements.toml:

[experimental_network]
enabled = true
allow_local_binding = true
allowed_domains = [localhost, 127.0.0.1]

C:\Users\<user>\.codex\config.toml:

[experimental_network]
enabled = true
allow_local_binding = true
allowed_domains = [localhost, 127.0.0.1]

[sandbox_workspace_write]
network_access = true

I also have localhost origins allowlisted in C:\Users\<user>\.codex\browser\config.toml:

[origins]
allowed = [
  http://localhost,
  http://127.0.0.1,
  http://localhost:4192,
  http://127.0.0.1:4192,
  https://localhost,
  https://127.0.0.1
]
denied = []

After restart, the current session context shows network access enabled and allowed for 127.0.0.1, localhost, but Browser Use still blocks both public URLs and localhost with the same enterprise network policy error.

This looks like Browser Use is not reading the configured network allowlist, or a higher-priority persisted/thread-level policy is overriding it. It also affects the Chrome plugin, not just the in-app Browser.

[LibraHo]

Additional update after more testing:

After reinstalling/restarting and switching Browser config from approval_mode = never_ask to approval_mode = ask, the Chrome backend is discoverable again and connects successfully.

Chrome plugin diagnostics all pass:

• Chrome is running
• Codex Chrome Extension is installed and enabled
• Extension version: 1.1.5_0
• Native host manifest is correct
• Registry path is correct
• The expected allowed origin is present: chrome-extension://hehggadaopoacecdllhhajmbjkdcmajg/

Codex can connect to the Chrome backend:

browser: Chrome
type: extension
profile: my Chrome profile
connected: true

However, navigation is still blocked for every tested URL:

https://example.com
http://127.0.0.1:4192/public/admin/index.html#dashboard
http://localhost:4192/public/admin/index.html#dashboard

All fail with the same error:

Browser Use rejected this action due to browser security policy.
Reason: Browser Use cannot access <url> because enterprise network policy blocks it.

So at this point the issue does not appear to be Chrome extension installation, native host setup, or localhost reachability. The extension/backend is working, but Browser Use's policy gate is still denying all navigation, including public websites.

My Codex app version is:

OpenAI.Codex 26.519.11010.0

[xuanxuan321]

me too

[LibraHo]

Follow-up after updating to the new Codex Desktop release from yesterday: this is still not resolved on my Windows machine.

Current status after the update:

• Chrome backend is still discoverable and connects successfully.
• Chrome extension diagnostics still pass.
• The machine is still a personal Windows PC, not an enterprise-managed device.
• Browser navigation is still blocked with the same Browser Use security / enterprise network policy error.
• The block still applies even to public URLs and localhost / 127.0.0.1.

I also found a closely related issue: #21955, where Chrome connects but navigation is blocked because network_access persists as false. That sounds very close to this failure mode. If this policy check is reading the thread sandbox network flag, it may be incorrectly blocking Browser Use navigation even when the browser backend itself is healthy.