Today in the middle of a presentation: „Windows 8 will restart in 15 minutes.“ As a matter of fact, this cannot be stopped, nor delayed. Microsoft, are you crazy?
It turns out that using gpedit.msc the automatic restart can be disabled. To do this, you have to activate (!) the option to not automatically restart after a software update. Alternatively, you can just disable automatic updates. I fear that most users will chose this insecure option if they need their computer for presentations. What a nuisance!