How to Fix Teams and Outlook Not Opening on an ARM Windows PC

Microsoft Teams or the new Outlook opens for a second and closes, or never appears at all, on a Surface Pro 11, Surface Laptop 7, or another ARM-based Windows 11 PC. Word, Excel, and classic Outlook still work. Reinstalling the apps does not help because the apps are not the problem. The August 2026 Windows security update broke a component those two apps depend on, mostly on new or freshly reset PCs, and the September 8 update fixes it.

Check whether the September update is already installed

Open Settings, then Windows Update, then Update history. Under Quality Updates, look for KB5124008 on Windows 11 24H2 or 25H2, or KB5124012 on 26H1, dated September 8, 2026 or later.

If it is listed and the apps still fail, skip to the Store step below. If the newest entry is an August update such as KB5121003 or KB5121000, continue.

Install the September update

Go back to Windows Update and click Check for updates. Let it download everything offered, then click Restart now when it asks.

After the restart, open Settings, System, About and check the build. It should read 26100.9445 on 24H2, 26200.9445 on 25H2, or 28000.2954 on 26H1, or a higher number. Open Teams or Outlook again.

Update the Auto Super Resolution package from the Store

If the update is not offered yet, or you are on a work PC where IT controls updates, Microsoft's documented workaround is a Store update rather than a Windows one.

Open Microsoft Store, click Downloads in the left sidebar, then click Check for updates. Install everything it finds. The one that matters is called Auto Super Resolution Package, and it needs to be version 1.0.19.0 or later. If it does not appear, search the Store for that name and open its page to update it there.

Open Teams and Outlook again

Launch each app from the Start menu. If either one was still running in the background when you installed the update, restart the PC once so the updated component is the one that loads, then try again.

If that fails. Confirm the PC is actually ARM-based under Settings, System, About, where System type should say ARM-based processor. On an Intel or AMD PC this fix does not apply, and a plain repair of the app from Settings, Apps, Installed apps is the next thing to try.

If classic Outlook works but the new one does not. That matches this bug exactly. Keep using classic Outlook until the September update or the Store package is in place; there is no need to switch back permanently.

Do not uninstall the August security update. It also carries security fixes, and the September update replaces it anyway. The Store package is the safe workaround while you wait.