How to detect whether you are in Windows PE
If you are developing a custom deployment solution you may need to have a way of determining whether or not you are currently running in Windows PE or in a full installation of Windows. The simplest way to do this is to query for whether the following registry key is present or not:
Mitch Tulloch is a seven-time recipient of the Microsoft Most Valuable Professional (MVP) award and widely recognized expert on Windows administration, deployment and virtualization. For more tips by Mitch you can follow him on Twitter or friend him on Facebook.