So on my cousins desktop there was a notice saying to update from win 8 to win 8.1 So I started it after a while the update said i needed to restart, after the restart there was a % that went to 100% . After hitting 100% The screen went black and there is an icon that looks like _ blinking over and over again in the top left corner. This has been going on for a good 45 mins. The keyboard and mouse are unresponsive during this. Should i restart the computer or wait for it to finish.