eliteHW has posted a review on Windows Preinstallation Environment (WinPE)

WinPE lets you create (diskpart.exe) and format (format.com) disk partitions, and gives you access to both NTFS file system partitions (with some constraints) and your internal network. The environment supports all mass storage devices that use Windows 2000 or Windows XP drivers, and you can incorporate additional drivers as new devices become available.

Using WinPE allows 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 you manufacture, and you will no longer need to request 16-bit drivers from independent hardware vendors (IHVs).

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