Windows app sends only the first message in every Codex chat

What issue are you seeing?

In every new Codex chat in the Windows desktop app, I can send the first message successfully and receive a response. After that, the message composer becomes stuck and the second message cannot be sent.

If I create another new chat, I can again send exactly one message, after which the same issue occurs. I am also unable to continue existing chats.

The issue often occurs immediately after starting Windows and opening the app. If the app works correctly at startup, it usually continues working during that session.

Steps to reproduce

1. Open the ChatGPT/Codex Windows desktop app.

2. Open an existing project or create a new empty project.

3. Start a new Codex chat.

4. Send a simple first message.

5. Wait for Codex to respond.

6. Attempt to send a second message.

7. The second message remains stuck and is not submitted.

Expected behavior

Multiple messages should be sent normally within the same Codex chat.

Troubleshooting already completed

• ChatGPT web works normally with the same account.
• Reproduced in a completely new and empty project.
• Restarted the app and Windows multiple times.
• Ran Workspace Diagnose.
• Signed out and signed back in.
• Deleted and recreated the .codex directory.
• Completely uninstalled and reinstalled the Windows app multiple times.
• Tested different VPN servers.
• Tested v2rayN using TUN and Global mode.
• Confirmed that WinGet and Microsoft Store sources update successfully.

A clean reinstall previously resolved the issue temporarily, but it returned after several days. After the most recent clean reinstall, the problem occurred immediately.

Environment

ChatGPT/Codex app version: 26.909.22227
Operating system: Windows 10 Pro, version 22H2
OS build: 19045.6466
Architecture: x64

Previous OpenAI Support Case: 14284642

OpenAI Support directed me to file this GitHub issue and attach a minimal reproduction log.

Start by reproducing the second-message failure in the Windows desktop app using the listed steps, then inspect the minimal reproduction log and the .codex state after the first response. The issue is done when new and existing Codex chats can submit multiple messages normally on the reported Windows environment.