Microsoft Teams, Outlook fail to launch on ARM-based Windows PCs

Microsoft is working to fix a known issue that causes crashes and launch failures for Microsoft Teams and New Outlook users after installing updates released since the August 2026 Patch Tuesday.

These issues affect only ARM-based Windows devices like the Surface Laptop 7 and Surface Pro 11 that run Windows 11 24H2 or later, and they mainly impact users who haven't installed Microsoft Store updates yet.

"After installing Windows security updates released on or after August 11, 2026, (KB5121003), Microsoft Teams and the new Outlook for Windows might fail to launch or might close unexpectedly on ARM-based devices, such as Surface Pro 11 and Surface Laptop 7," Microsoft said in a Windows release health update.

"Classic Outlook, Word, Excel, and other applications are not known to be affected. This issue is most likely to occur on new or freshly imaged PCs that have not yet installed any Microsoft Store updates."

While Microsoft didn't share the root cause, it advised affected customers to update the Auto Super Resolution Package, which the company says allows "Copilot+ PCs to use AI to make supported games play more smoothly with enhanced details."

Although Microsoft did not disclose the root cause, it advised affected customers to update the Auto Super Resolution Package as a temporary workaround. According to Microsoft, this package enables Copilot+ PCs to use AI to make gameplay smoother.

To do that, users have to open the Microsoft Store, go to Downloads > Check for updates, and install Auto Super Resolution Package version 1.0.19.0 or later.

Microsoft says that it's now working on a permanent fix for this issue, which will be released with a future Windows update.

This is the latest in a series of known issues caused by Windows updates released in August. For instance, last week, Microsoft also confirmed that August 2026 .NET Framework updates are breaking printing and PDF export in some applications.

Days later, it also began rolling out a fix for a known issue caused by peripherals with built-in RGB lighting that triggered system crashes and gaming issues on Windows 11 devices with EXCEPTION_ACCESS_VIOLATION" errors.

On Friday, the company also asked customers to ignore alerts that Microsoft Defender Antivirus has been turned off after installing the latest Defender updates.