Microsoft resolves startup crashes for Teams and Outlook on ARM devices after August updates
A known issue prevented Microsoft Teams and the new Outlook for Windows from launching on ARM-based PCs running Windows 11 24H2 or later, particularly on fresh installations that lacked Microsoft Store updates. The problem emerged after security updates released on or after August 11, 2026, and was addressed in the September 2026 Patch Tuesday cumulative update KB5124012. Microsoft recommends installing the latest update to apply the fix.
The launch failures specifically targeted ARM-based Copilot+ PCs like the Surface Pro 11 and Surface Laptop 7 running Windows 11 24H2. Freshly imaged systems without recent Microsoft Store updates were most vulnerable. Microsoft initially suggested updating the Auto Super Resolution Package as a stopgap measure.
The permanent fix arrived with the September cumulative update KB5124012. This incident follows a string of August update complications, including .NET Framework printing errors, RGB peripheral crashes, false antivirus alerts, and wiped desktop settings.
For organizations deploying ARM-based Windows devices, this recurring patch-related instability could disrupt daily communication workflows, particularly for remote teams reliant on Teams and Outlook. The need for Store updates alongside system patches may complicate IT management, potentially leading to delayed update rollouts. If similar issues continue, it could erode confidence in the monthly Patch Tuesday cadence, prompting stricter pre-deployment testing in enterprise environments.