Codex Desktop conversation can corrupt Windows AppX package state

[Bl0ck154]

Summary

Opening one existing Codex Desktop project conversation can crash/disappear the desktop app and leave the Windows AppX package in a broken state. After this happens, the app no longer launches until the local desktop web profile is quarantined and the Microsoft Store package is reinstalled.

This is a critical data/state handling bug: a single stale/corrupt conversation/browser-sidebar state should not be able to poison the whole desktop app or the Windows package launch state.

Environment

• App: OpenAI.Codex / Codex Desktop from Microsoft Store
• Package: OpenAI.Codex_26.721.4979.0_x64__2p2nqsd0c76g0
• Version: 26.721.4979.0
• OS: Windows 10 22H2
• Install source: Microsoft Store product 9PLM9XGG6VKS

Impact

• The app initially opens the existing conversation.
• Shortly after, the desktop app disappears/crashes.
• Windows marks the package as Modified, NeedsRemediation.
• Subsequent launches fail with AppModel error 0x3CFC until reinstall.
• Normal app restart does not recover it.

Expected Behavior

If a conversation's local desktop state, browser sidebar state, or embedded browser session is stale/corrupt, Codex Desktop should handle it gracefully:

• Show a recoverable error for that conversation.
• Allow the user to reset only that conversation's local desktop state.
• Keep the app launchable.
• Never leave the Microsoft Store/AppX package in NeedsRemediation because of one conversation state.

Actual Behavior

Opening the affected existing conversation triggers a browser sidebar/webview restore path, then logs Conversation state not found, then a Chromium GPU child process crash/launch-failure. After this, Windows AppModel reports launch failure and the AppX package state becomes broken.

Relevant Sanitized Logs

Codex Desktop logs around the crash:

IAB_LIFECYCLE registered browser sidebar thread conversationId=<redacted>
IAB_LIFECYCLE renderer created browser sidebar webview ... initialUrl=https://dash.cloudflare.com/login
maybe_resume_started conversationId=<redacted>
response_routed ... method=thread/read
response_routed ... method=thread/resume
error [electron-message-handler] Conversation state not found conversationId=<redacted> rendererWindowAppearance=avatarOverlay
warning Recoverable Chromium child process gone exitCode=101457950 processType=GPU reason=crashed serviceName=GPU
warning Recoverable Chromium child process gone exitCode=18 processType=GPU reason=launch-failed serviceName=GPU

Windows AppModel logs after the crash:

0x3CFC: Cannot create the process for package <NULL> because an error was encountered while checking the machine-level package status. The application cannot be started. Try reinstalling the application to fix the problem.

Package state after the crash:

Name         PackageFullName                               Status
OpenAI.Codex OpenAI.Codex_26.721.4979.0_x64__2p2nqsd0c76g0 Modified, NeedsRemediation

Recovery / Workaround

The only reliable local workaround so far:

1. Quarantine %APPDATA%\Codex\web.
2. Reinstall the Microsoft Store package.
3. Avoid reopening the same problematic conversation.

After quarantine + reinstall, the package returns to Status: Ok and the app launches again. Reopening the same conversation reproduces the failure.

Request

Please fix the Codex Desktop conversation/browser-sidebar resume path so stale or corrupt conversation-local browser state cannot crash the app or corrupt the AppX launch state. A safe UI/CLI option to reset only one conversation's local desktop/browser-sidebar state would also make this recoverable without full reinstall.

[github-actions]

Potential duplicates detected. Please review them and close your issue if it is a duplicate.

• [Windows Desktop 26.721.4979.0] Session restore should quarantine failed in-app-browser state instead of terminating Codex #35475
• [Windows Desktop] Repeated GPU process crash (exitCode=101457950) after update, AppX breaks into NeedsRemediation state #35566
• [Windows Desktop] Window disappears, residual processes block relaunch, GPU process crashes, and AppX registration repeatedly breaks #35465

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[Bl0ck154]

Additional context on user impact:

This failure was not just a simple app crash. It cost roughly two hours to diagnose and recover because the crash left the Microsoft Store/AppX package in a broken state and the normal reinstall path was unreliable.

The recovery involved a painful loop of:

• App disappears after opening the affected conversation.
• Package becomes Modified, NeedsRemediation.
• Launch fails with AppModel 0x3CFC.
• Microsoft Store/App Installer reinstall initially got stuck during download/install progress instead of cleanly repairing the package.
• The Store/App Installer pipeline had to be repaired/reset before reinstall would complete.
• Local Codex desktop web profile had to be quarantined.
• Codex had to be reinstalled again.
• The same conversation then reproduced the breakage.

From a user perspective, this is extremely frustrating because one conversation state effectively turns into a desktop app + Windows Store repair problem. A user should not need to troubleshoot AppX remediation, Store download state, and local Electron/Chromium profile state just because one Codex conversation has stale/corrupt browser-sidebar state.

Please treat this as more than a cosmetic crash. The current failure mode wastes a lot of time and makes the product feel unsafe to use with existing project conversations, because reopening one bad thread can break the entire desktop app again.