Try pushing one of the buttons on the top edge of the tablet. On T201 tablets, push the SAS button on the right edge. If this does not work, you may have to take the battery out and let it rest for about 30min before the tablet will come back on. This may mean that the tablet has overheated and shut down. Especially if you are in a hotter area, make sure that the IQ is kept cool, especially if it is running for an extended period of time. Overheating of the tablet can cause other problems such as screen cracking, so it is important to always keep your tablet from overheating.