An hour ago my Surface went dark while copying files. It didn't go to sleep, it just quit. It will not wake up and the power button does nothing, no matter how long I hold it down, hoping to force it to shut down and reboot. This happens all too frequently and, eventually, it comes to life again. I'm not sure if it just goes to sleep or if it simply shuts down. If it went to sleep it should wake up when I tap the keys but it doesn't. If it shut down it should start when I press the power button, but it doesn't, until it's ready. I imagine it might be updating so won't allow me to wake it or reboot it but usually there is a message advising that it is updating and "do not turn off". Eventually, it comes to life again, or it has in the past, but it's been almost 2 hours since it went off and I'm beginning to worry! I this something peculiar to the Surface computer? This has never happened with my other computers.