This is a historical Windows 11 build 22631.3520 outcome with a specific WinForms trigger. It does not mean that every UNEXPECTED_KERNEL_MODE_TRAP is fixed by that old cumulative update.

  • A reproducible WinForms UI action caused UNEXPECTED_KERNEL_MODE_TRAP on affected Windows 11 builds.
  1. Installed KB5036980, updating Windows to build 22631.3520.

Reported outcome: The original poster verified the crash was fixed; another team could no longer reproduce it.

Check the exact affected build and applicable Microsoft servicing information. Use the appropriate superseding correction for the installation, rather than installing an obsolete or mismatched package.