Win32 blocking feature

Starting with Windows 10 build number 15042, Microsoft will allow administrators to block the installation of Win32 applications on their computer.

This new feature, spotted by Vitor Mikaelson, will be available for all Windows 10 editions and will come with a corresponding configuration option in the Windows 10 Apps & Features settings screen.

Win32 blocking feature
Win32 blocking feature (Source: Vitor Mikaelson)

Win32, also known as the Windows API, is the core technology that used to power the entire app ecosystem in older Windows versions, up until Windows 10, when Microsoft introduced its replacement, the Universal Windows Platform (UWP).

UWP apps work across all modern Microsoft products, from phones to gaming consoles, and are considered more secure, since they work in their own, self-contained security sandbox, preventing the app from reaching core Windows functions.

After the release of Windows 10, Microsoft continued to support older Win32 apps, so as not to kill its entire apps ecosystem in one blow, something that would have been catastrophic and deterred many users from migrating to Windows 10, to begin with.

Nevertheless, Microsoft still sees Windows' future in UWP apps. Earlier this months, ISOs for Windows Cloud leaked online, a version of the Windows 10 operating system that works only with Windows Store (UWP-compatible) apps, similar to how Windows RT worked.

Blocking Win32 apps improves security

The advantage of this Win32 app blocking feature is its security implications. Unsandboxed Win32 apps are the main source of viruses and malware on Windows 10.

This upcoming feature can be a godsend for system and network administrators in enterprise environments, as it would allow them to permit users to install the apps they need on their own, but restrict installations only to safe Windows Store apps.

Even better is that having this feature turned on only blocks the installation of Win32 apps, and not the ability to run Win32 apps. Sysadmins can install verified Win32 apps, turn on the installation filter, and still allow users to run Win32 apps.

This Win32 installation blocking system is slated to arrive with Windows 10 Creators Update, expected for April 2017.