[Windows Desktop 26.1021.31345] Chat mode missing, Codex workspace settings fail — HTTP 403 cloudflare_challenge

ChatGPT Bugs
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Environment

  • Surface: Windows 11 (ChatGPT desktop application)

  • Browser or app version: 26.1021.31345

  • Subscription: ChatGPT Plus

  • Region: Slovakia

  • Affected feature: Regular Chat mode, Codex workspace settings, conversation initialization

Bug

Since approximately October 24–25, 2026, the ChatGPT Windows desktop application has become partially unusable following a recent update.

Actual behavior:

  • Regular Chat mode has completely disappeared from the application. Only Work and Codex are available.

  • Opening Codex displays the error: “Couldn’t load workspace settings.”

  • Various error popups appear briefly and disappear almost immediately.

  • The problem persists after restarting the application and signing out and back in.

Expected behavior:

The Windows application should provide all three modes (Chat, Work, Codex), load workspace settings correctly, and allow normal conversations.

Additional observations:

  • The same issue occurs on two separate Windows computers connected to the same home network.

  • ChatGPT works normally in a web browser, including a fresh private browsing session.

  • The official ChatGPT Android application works normally on the same Wi-Fi network, with conversations synchronizing correctly.

  • Restarting the router did not resolve the issue.

This appears to be isolated to the Windows desktop application rather than the ChatGPT account or service in general.

Reproduction

  1. Launch ChatGPT for Windows (v26.1021.31345).

  2. Observe that regular Chat mode is missing; only Work and Codex are available.

  3. Switch to Codex.

  4. Observe the “Couldn’t load workspace settings” error.

  5. Try restarting the application or signing out and back in — the issue persists.

  6. Open ChatGPT in a web browser or the Android application using the same account and network — regular Chat works correctly.

Troubleshooting attempted:

  • Restarted the desktop application.

  • Signed out and back in.

  • Switched between Codex and ChatGPT, creating new conversations.

  • Tested the web interface in private browsing mode.

  • Reproduced the issue on a second Windows computer.

  • Restarted the home router.

None of these steps resolved the Windows desktop issue.

Diagnostics

Exact error:

The application’s diagnostic logs show numerous HTTP 403 responses with errorCode=cloudflare_challenge across multiple API endpoints.

GET  /settings/user                 → 403 cloudflare_challenge
GET  /accounts/check/v4-2023-04-27  → 403 cloudflare_challenge
POST /conversation/init             → 403 cloudflare_challenge
GET  /models                        → 403 cloudflare_challenge
GET  /system_hints                  → 403 cloudflare_challenge

Authentication itself appears successful:

authenticatedAccountPresent=true
authMethod=chatgpt
result=succeeded

This suggests that the application recognizes the authenticated account, but subsequent requests are rejected by the server-side challenge mechanism.

When it happened (with timezone) and how often:

  • First noticed: October 24–25, 2026.

  • Confirmed in diagnostic logs: October 25, 2026, at approximately 09:17 CET (UTC+1).

  • Frequency: Persistent and reproducible on both Windows devices.

Possible cause:

A regression in the Windows desktop application or an incompatibility with Cloudflare challenge handling. The available logs do not establish whether the underlying problem is client-side or server-side.

Is anyone else experiencing this with the current Windows release? Is there a known workaround or an upcoming fix?

I can provide additional redacted diagnostic logs if needed.