GoKawiilMicrosoft confirms Teams, New Outlook crash on ARM Windows PCs after August update
Microsoft says its August 11, 2026 security update (KB5121003) is causing Teams and New Outlook to fail to launch or crash unexpectedly on ARM-based Windows 11 24H2 devices like the Surface Pro 11 and Surface Laptop 7. The problem mostly hits new or freshly imaged machines that haven't yet grabbed Microsoft Store updates, while Classic Outlook, Word and Excel remain unaffected.