Microsoft Windows Preinstallation Environment (Windows PE) is a minimal Win32 subsystem with limited services, based on the Windows XP Professional kernel running in protected mode. It contains the minimal functionality that you need to run Windows Setup, install an operating system from a network share, automate basic processes, and perform hardware validation.

Incorporating Windows PE into your factory preinstallation process enables you to port your existing MS-DOS-based tools to a subset of the 32-bit Windows APIs, so you can more easily maintain these applications in a standard development environment, such as Microsoft Visual Studio. These hardware diagnostics and other preinstallation utilities can then use the same signed Windows XP drivers in the computers that you manufacture, and you will no longer need to request 16-bit drivers from independent hardware vendors (IHVs).