New Chat and Existing chats open but replying returns "Request failed with status 403".

Open 💬 9 comments Opened Jul 12, 2026 by llima3000
💡 Likely answer: A maintainer (github-actions[bot], contributor) responded on this thread — see the highlighted reply below.

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

Version 26.707.51957

What subscription do you have?

GO

What platform is your computer?

MAcOS

What issue are you seeing?

Problem:

  • New Task works.
  • New Chat returns "Request failed with status 403".
  • Existing chats open but replying returns "Request failed with status 403".
  • Same account and same conversations work normally in ChatGPT Web.

<img width="1265" height="795" alt="Image" src="https://github.com/user-attachments/assets/27e1c1fa-f7db-4b22-b47d-174b9aad7207" />

What steps can reproduce the bug?

After I installed the new application, the error is always there, it doesn't matter if I reinstall the app, do the login, or clear the caches

What is the expected behavior?

_No response_

Additional information

_No response_

View original on GitHub ↗

9 Comments

LutzRFrank · 8 days ago

Same here (019f55fa-e530-7e00-a7fe-c96e3c0b1bd6) since a few hours

<img width="1297" height="872" alt="Image" src="https://github.com/user-attachments/assets/cc4d89a0-7900-4d31-92d5-b97c777bc679" />

Subject: 403 error when creating a normal ChatGPT conversation in the macOS Codex app
Creating a normal ChatGPT conversation in the macOS Codex app via Option–Command–N consistently returns HTTP 403. Codex tasks still work normally, and the ChatGPT app on my iPhone works with the same account.
The macOS log shows: “Unusual activity has been detected from your device. Try again later.”
I have not used automation or generated unusual traffic; I only communicated normally through Codex. Please check whether my macOS app session or device was incorrectly flagged.
OpenAI request ID: c2abbb80-b092-4e92-b364-e31a06eb67ae
Earlier request ID: 93ae1cb6-2c0a-4de9-9cd7-d7ad55ec5d88
Date: July 12, 2026
Region/time zone: Germany, Europe/Berlin
Please let me know whether I should reset the local app session or wait for a server-side restriction to be removed.

github-actions[bot] contributor · 8 days ago

Potential duplicates detected. Please review them and close your issue if it is a duplicate.

  • #32552

Powered by Codex Action

LutzRFrank · 8 days ago

This appears to be the same issue as #32552. I’m using the same Codex app version (26.707.51957) on macOS and receive the identical “Unusual activity has been detected from your device” response. Regular Codex tasks and ChatGPT on iPhone continue to work.

thomas-dam · 8 days ago

I can reproduce:
ChatGPT for macOS 1.2026.183
Plus subscription
macOS 26
Reproduced on a second Mac (1.2026.153)
Existing conversations work.
Any new conversation fails, including a first message containing only hello.
Browser (same account, same machine, same network) works normally.
Reinstall and re-authentication do not change the behavior.
Performance trace uploaded: no-active-thread-019f5602-3332-7ad3-bc5e-461b73eee2de

llima3000 · 8 days ago

For me, it started as issue #32552 in the older app/ I removed everything and cleaned the library caches too. Reinstalled the new app and got Codex instead of the old interface. It's fine since it looks like any other harness app

The main issue is that when I tried to open new chats or access the historic ones, I'm getting the 403.

coffnix · 8 days ago

The old macOS app stopped working about an hour ago, and all of the apps on all of my iPhones also stopped working.

<img width="1202" height="872" alt="Image" src="https://github.com/user-attachments/assets/d1b62c58-3477-47dc-b56c-f261187ac7bc" />

<img width="660" height="1434" alt="Image" src="https://github.com/user-attachments/assets/f4cfbfc3-f43e-42a3-a2c6-07c82818419f" />

daslicht · 8 days ago

nice to see that I am not the only one <3

coffnix · 8 days ago
nice to see that I am not the only one <3

stopped after this: https://help.openai.com/en/articles/20001276-moving-to-the-new-chatgpt-desktop-app

xujia-debug · 8 days ago

Same issue lol, but now it already has been solved.