Today, I was working and got a pop-up that Norton wanted to install an update requiring a Windows restart. I did that and walked away for about 10 minutes. When I got back, I was at my Thinkpad's inital screen telling me to hit Enter if I wanted to prevent the system from starting Windows. The system had crashed. I force-turned it off. When I turned it on again, the same thing happened. The Enter key did nothing. After trying this several times, I thought that the Norton Update might have affected the BIOS. I turned off the system and disconnected everything, When I came back several hours later, luckily everything worked again.
Fortunately, my deadline work was finished this morning. If this had happened yesterday, I would have been severely inconvenienced. There is no reason for updates to crash a system like that.