Laptop Sleep Versus Shutdown after a Windows Upgrade Failure

I have a Dell XPS laptop running Windows 7. Recently, MS pushed out an update which, for some reason, never really completed - I was left with a message about Windows shutting down after the upgrade was complete.  I had left the machine on to perform the upgrade overnight, so it was a surprise to see this the next morning.

Well, not figuring out anything else to do, I pushed the power off button and then again to restart the laptop. Every time I did this, I would end up at the same place - with the message that Windows would restart after is was complete. I tried to get into safe startup mode (F8), but that never worked. I was getting a little concerned and called an IT guy to help.

He suggested that when I power off the laptop, I hold the power button down and not just press it. Well, that worked fine. I should have realized it, but simply pressing the power button puts the laptop in sleep or hibernate mode and then pressing it again starts back where it was left off. I knew how this worked in normal operations, but was surprised (though shouldn't have been?) to find the same during an update. So - lesson learned...