[Windows] ChatGPT 26.820.60940 fails with "invalid transport in mcp_servers.codex_app"; Beta 26.727.40816 works

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

Version 26.820.60940

What subscription do you have?

Pro

What platform is your computer?

Microsoft Windows NT 10.0.26200.0 x64

What issue are you seeing?

Stable app version

ChatGPT / Codex & OWL 26.820.60940
Released Aug 25, 2026
MSIX package version: OpenAI.Codex 26.820.7780.0

Working comparison version

ChatGPT (Beta) / Codex & OWL 26.727.40816
Released Jul 30, 2026

Platform

Windows 11 Home 10.0.26200 Build 26200, x64
Dell XPS 16 (Dell 16 Premium) DA16250
Intel Core Ultra 7 255H
32 GB RAM
WSL/Ubuntu workspace

Issue

Immediately after updating Stable to 26.820.60940, Codex Desktop can no longer start or resume chats in my WSL project.

The application displays:

ChatGPT can't load config.toml, so this thread can't resume.

Fix config.toml: invalid transport in mcp_servers.codex_app

After saving the file, reopen the thread.

The same error occurs when creating a completely new chat, so this is not limited to existing thread state.

There is no [mcp_servers.codex_app] or [mcp_servers.codex_apps] entry in my user, system, or project TOML configuration.

I searched the active WSL config layers shown by /debug-config:

/etc/codex/config.toml
/home//.codex/config.toml
/home//Development/ETL - WSL/.codex/config.toml

and none contain codex_app or codex_apps.

I also tested:

features.apps = false

and disabled codex-app-tools; neither changes the error.

Important isolation tests

Standalone Codex CLI 0.145.0 inside WSL loads the same project successfully.
Stable Desktop bundles codex-cli 0.150.0-alpha.8.
I manually launched that exact bundled 0.150.0-alpha.8 executable against the same WSL workspace and it also starts successfully.
ChatGPT Beta 26.727.40816 works successfully with the same project/configuration.
Only ChatGPT Stable 26.820.60940 produces invalid transport in mcp_servers.codex_app.

This appears to indicate that Desktop 26.820.60940 is supplying or generating an invalid runtime MCP configuration when launching Codex, rather than the invalid configuration coming from config.toml.

Expected behavior

Stable should load the same workspace and configuration that Beta 26.727.40816 and standalone Codex successfully load.

What steps can reproduce the bug?

Stable app version

ChatGPT / Codex & OWL 26.820.60940
Released Aug 25, 2026
MSIX package version: OpenAI.Codex 26.820.7780.0

Working comparison version

ChatGPT (Beta) / Codex & OWL 26.727.40816
Released Jul 30, 2026

Platform

Windows 11 Home 10.0.26200 Build 26200, x64
Dell XPS 16 (Dell 16 Premium) DA16250
Intel Core Ultra 7 255H
32 GB RAM
WSL/Ubuntu workspace

Issue

Immediately after updating Stable to 26.820.60940, Codex Desktop can no longer start or resume chats in my WSL project.

The application displays:

ChatGPT can't load config.toml, so this thread can't resume.

Fix config.toml: invalid transport in mcp_servers.codex_app

After saving the file, reopen the thread.

The same error occurs when creating a completely new chat, so this is not limited to existing thread state.

There is no [mcp_servers.codex_app] or [mcp_servers.codex_apps] entry in my user, system, or project TOML configuration.

I searched the active WSL config layers shown by /debug-config:

/etc/codex/config.toml
/home//.codex/config.toml
/home//Development/ETL - WSL/.codex/config.toml

and none contain codex_app or codex_apps.

I also tested:

features.apps = false

and disabled codex-app-tools; neither changes the error.

Important isolation tests

Standalone Codex CLI 0.145.0 inside WSL loads the same project successfully.
Stable Desktop bundles codex-cli 0.150.0-alpha.8.
I manually launched that exact bundled 0.150.0-alpha.8 executable against the same WSL workspace and it also starts successfully.
ChatGPT Beta 26.727.40816 works successfully with the same project/configuration.
Only ChatGPT Stable 26.820.60940 produces invalid transport in mcp_servers.codex_app.

This appears to indicate that Desktop 26.820.60940 is supplying or generating an invalid runtime MCP configuration when launching Codex, rather than the invalid configuration coming from config.toml.

Expected behavior

Stable should load the same workspace and configuration that Beta 26.727.40816 and standalone Codex successfully load.

What is the expected behavior?

It works. Threads load.

Additional information

No response

Reproduce with Stable 26.820.60940 in the WSL workspace and inspect the active layers reported by /debug-config. Compare Desktop's launch behavior with the bundled codex-cli 0.150.0-alpha.8 executable and Beta 26.727.40816, which both work. Done means Stable no longer reports invalid transport in mcp_servers.codex_app and can load or create chats.