Occasionally, PC's "lock up" or "freeze" during an operation and nothing can be done to unlock or unfreeze them. 

In order to get the PC back to a working state, disconnect the laptop from the docking station (if you have a system that has a docking station) and open the lid. 

Hold down the power button for about 20-30 secs, until the laptop completely shuts off. You will hear the fans turn off, and the lights under the keyboard go dark.

Wait about 1 minute, and then you may connect the laptop back up to the docking station, and the laptop will automatically power up.