This week, Microsoft finally released a new update for Windows Insiders in the Canary Channel. Build 25905 contains features Microsoft introduced earlier in the Dev Channel (Dev Drive, Windows Backup, Dynamic Lighting, redesigned File Explorer, and more), plus extra additions such as Fluent 3D Emojis, resurrected Zune drivers (yay), new features for the Microsoft Store, and Rust in the Windows Kernel for reliability and security improvements.
There is also one important change for those using Windows computers with ARM processors: starting with build 25905 (full release notes available here), Windows 11 no longer supports arm32 Univeral Windows Platform (UWP) applications.
Starting in this Insider Preview build in the Canary Channel, we have removed support for Arm32 UWP applications from Windows on Arm, as documented here: Windows 11 Specs and System Requirements. After the OS upgrade, any installed Arm32 applications will no longer launch on your device.
According to Microsoft, updating an ARM-powered Windows PC to Windows 11 build 25905 will prevent installed arm32 UWP applications from running. The change does not affect arm64 apps, plus users can take action to ensure their favorite programs continue operating after upgrading to build 25905 and newer.
Microsoft recommends Windows on ARM users install available updates from the Microsoft Store before upgrading to the latest Canary build. Also, during setup, Windows will display a list of currently installed arm32 applications you will not be able to open once the installation process is over. You can resolve this problem by deleting arm32 programs and reinstalling them using compatible binaries (if available) from the Microsoft Store.
You can check what platform your apps use by heading to Task Manager > Details > Architecture.
In case you missed it, Microsoft recently released firmware updates for the Surface Pro X device family with ARM processors. It aims to resolve camera issues first reported in May 2023. You can find more details about the latest Surface firmware here.