Checked October 11, 2026. Start with the vendor’s current documentation: Claude installation or Codex troubleshooting. A similar error in another app does not establish the same cause.
First identify the failure
| Symptom | Next check |
|---|---|
| No window / immediate exit | Record app version, Windows version, installer source and crash time. |
| “This app can’t open” | Check the installed package status and Windows application events. |
| Sign-in loop | Treat browser callback, network and account errors separately from launch failure. |
| Task stopped inside an open app | Check permissions and usage limits; this is not a startup failure. |
Work from least destructive to most disruptive
- Quit and restartSave work, quit only the affected app, then restart Windows if an update is pending.
- Update from the official sourceCheck supported Windows version and CPU architecture. Avoid unofficial mirrors or extracted old builds.
- Try Repair if offeredOpen Settings → Apps → Installed apps → the affected app → Advanced options → Repair. The option depends on installation type.
- Collect evidence if Repair failsOpen Event Viewer around the exact crash time. Record Application and CodeIntegrity events, package status and the named DLL. A 3033 event alone does not prove every launch failure has the same cause.
- Back up before Reset or reinstallReset can remove local settings and sessions. Preserve project files, configuration and relevant app data; verify account sync rather than assuming all history is recoverable.
- Escalate with logsUse the vendor support route with version, timestamp and reproduction steps. Remove tokens, personal paths and private conversations before sharing logs.
Get-AppxPackage *codex* | Select-Object Name, Version, Status
Get-WinEvent -LogName "Microsoft-Windows-CodeIntegrity/Operational" -MaxEvents 20 | Select-Object TimeCreated, Id, MessageThese commands are read-only. An empty Appx result can mean the app uses a different installer; it does not prove the app is missing. Log access may require administrator permission.
What not to do
Do not disable Memory Integrity or Code Integrity to make a DLL load. Do not block the update domain in hosts, take ownership of WindowsApps, or assume a non-MSIX build bypasses all security checks. Avoid moving sandbox data across drives with junctions. A packaging workaround is version-specific, not a permanent fix.
FAQ
Is every Windows launch failure the same MSIX bug?
No. Packaging, compatibility, policy, graphics and damaged installation state can cause similar symptoms. Match the diagnosis to your logs.
Will Repair always fix it?
No. Try Repair when available, then collect logs. Reset and reinstall are separate operations and may affect local data.
Should I disable security or automatic updates?
No. Keep security controls and updates enabled. Ask the vendor or administrator for a supported fix.