Windows Codex Desktop always uses retired gpt-5.3-codex model #31016

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

26.623.101652

What subscription do you have?

ChatGPT Plus

What platform is your computer?

"$([Environment]::OSVersion.VersionString) $([Environment]::Is64BitOperatingSystem)"

What issue are you seeing?

Feedback ID:
019f278e-e389-7f20-a39a-37f4f6db8b4b

Issue:

Every new conversation in the Windows Codex Desktop immediately fails with:

"The 'gpt-5.3-codex' model is not supported when using Codex with a ChatGPT account."

Environment:

• Codex Desktop 26.623.101652
• Windows 11
• ChatGPT Plus
• Logged in with ChatGPT account

What I tried:

• Reinstalled Codex
• Signed out and signed in again
• Started a brand-new conversation
• Tested with only "Hello"
• Verified ChatGPT Plus subscription
• Codex Cloud works correctly in the browser

Expected:

The desktop app should use the current supported model.

Actual:

The desktop app always attempts to use the retired gpt-5.3-codex model and every conversation immediately fails.

Feedback ID:
019f278e-e389-7f20-a39a-37f4f6db8b4b

What steps can reproduce the bug?

Feedback ID: 019f278e-e389-7f20-a39a-37f4f6db8b4b

What is the expected behavior?

Codex Cloud works correctly. Only the Windows Desktop app is affected.

Additional information

No response