Ah, we abused the way Windows stopped its processes during my high school days at the same time.
I don’t know exactly what Microsoft calls these processes, but basically it means that any SYSTEM owned processes that are not kernel related (such as school monitoring software that you as a user cannot shut down on your own) were the first to be closed when you pressed the ‘power’ button, and thus the userland processes. As a result, you may interrupt the computer shutdown by a Notepad or similar process. open it, tap something, press the power button, then when Windows asks you if you want to save or not, click Cancel.
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