Windows Codex App no longer shows gpt-5.5 after reinstall; CLI still has access
What version of the Codex App are you using (From “About Codex” dialog)?
26.429.3425.0 Package: OpenAI.Codex_26.429.3425.0_x64__2p2nqsd0c76g0 Installed via Microsoft Store / winget msstore.
What subscription do you have?
ChatGPT Plus
What platform is your computer?
Windows x64
What issue are you seeing?
After uninstalling and reinstalling the native Windows Codex App today, gpt-5.5 disappeared from the app's model picker.
My account definitely still has access to gpt-5.5. I have used gpt-5.5 in Codex since day one of release, and it was previously available in this same Windows Codex App. gpt-5.5 still works through Codex CLI on the same PC and same account.
Before I changed my config back to gpt-5.4, my Codex config still pointed to gpt-5.5. When I tried to use the app, I got this error:
{"type":"error","status":400,"error":{"type":"invalid_request_error","message":"The 'gpt-5.5' model requires a newer version of Codex. Please upgrade to the latest app or CLI and try again."}}
However, the app appears to already be on the latest Microsoft Store version:
OpenAI.Codex 26.429.3425.0
OpenAI.Codex_26.429.3425.0_x64__2p2nqsd0c76g0
winget upgrade Codex -s msstore reports:
No available upgrade found.
No newer package versions are available from the configured sources.
This looks like a Windows Codex App model-picker / app-version-gating issue, not an account entitlement issue, because gpt-5.5 still works in Codex CLI on the same machine and account.
What steps can reproduce the bug?
Uploaded thread: f858b2cf-3c00-4996-a6a2-60f8e92dddc4
Steps:
- Use an account that has access to gpt-5.5.
- Verify that gpt-5.5 works in Codex CLI on the same Windows machine.
- Install or reinstall the native Windows Codex App from Microsoft Store / winget msstore.
- Open the Windows Codex App and sign into the same account.
- Open the model picker.
- Observe that gpt-5.5 is missing from the model picker.
- If config.toml still contains model = "gpt-5.5", try using the app.
- The app returns:
{"type":"error","status":400,"error":{"type":"invalid_request_error","message":"The 'gpt-5.5' model requires a newer version of Codex. Please upgrade to the latest app or CLI and try again."}}
Expected result:
gpt-5.5 should appear in the Windows Codex App model picker, as it did before reinstalling the app.
Actual result:
gpt-5.5 is missing from the Windows Codex App model picker, even though it works in Codex CLI on the same PC/account.
What is the expected behavior?
_No response_
Additional information
Troubleshooting already tried:
- Reinstalled the Windows Codex App.
- Reset/cleared app cache.
- Changed config.toml from model = "gpt-5.5" to model = "gpt-5.4" to avoid the startup error.
- Confirmed installed app package version:
Name Version PackageFullName
OpenAI.Codex 26.429.3425.0 OpenAI.Codex_26.429.3425.0_x64__2p2nqsd0c76g0
- Confirmed winget sees the same version:
Name Id Version Source
Codex 9PLM9XGG6VKS 26.429.3425.0 msstore
- Confirmed there is no Store update available:
winget upgrade Codex -s msstore
No available upgrade found.
No newer package versions are available from the configured sources.
- Tried aggressive local reset:
Get-Process Codex -ErrorAction SilentlyContinue | Stop-Process -Force
Rename-Item "$env:LOCALAPPDATA\Packages\OpenAI.Codex_2p2nqsd0c76g0" "OpenAI.Codex_2p2nqsd0c76g0.bak" -ErrorAction SilentlyContinue
Rename-Item "$env:USERPROFILE\.cache\codex-runtimes" "codex-runtimes.bak2" -ErrorAction SilentlyContinue
Rename-Item "$env:USERPROFILE\.codex\.tmp" ".tmp.bak2" -ErrorAction SilentlyContinue
None of this restored gpt-5.5 in the Windows Codex App model picker.
4 Comments
Potential duplicates detected. Please review them and close your issue if it is a duplicate.
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This may be related to / duplicate of #19404.
I am leaving this issue open for now because my case has a few extra details that may help triage:
{"type":"error","status":400,"error":{"type":"invalid_request_error","message":"The 'gpt-5.5' model requires a newer version of Codex. Please upgrade to the latest app or CLI and try again."}}
I am fine with this being closed as a duplicate if #19404 is the main tracking issue, but I wanted to provide the reinstall/WSL-mode/version-gating details because they may point to persistent Windows App state or an app-specific model filter.
I'm running into another facet of what seems to be the same issue.
When I started a new chat after installing, my selected model says "Custom" and I'm not able to select another model (attempting to do so does nothing). When I send a message, I get the following error:
{"type":"error","status":400,"error":{"type":"invalid_request_error","message":"The 'gpt-5-codex' model is not supported when using Codex with a ChatGPT account."}}
However, after sending that first message, I can select 5.5 in the model menu within that same chat and it properly switches to 5.5 (and no longer says "Custom"). Sending a message in the same chat then works properly.
I'm currently using the Codex Windows app, version 26.429.30905
I've resolved the issue. I just completely wiped absolutely all vestiges of Codex App (including CodexCLI itself) from my PC by diligently following instructions from CodexCLI.
All my chats are gone. But it was completely worth it. (thankfully, i've backed up the skills and was able to restore them)
One more note. Changing from Windows Native to WSL in the options should Not just totally brick the app with no ability to restore it (even by fully reinstalling it). And no, it wasn't as simple as changing a line in config.toml
I'm no coder, but i'm pretty technically inclined. And it was a freaking nightmare. Any normal person in my place would have given up long ago.
Terrible user experience tbh.