I have bought a Xbox One from Target and it worked fine until today. The Kinect just turns off itself suddenly and the top right of the HDTV screen say that your Kinect is unplugged. It seems to be a common problem.
My Kinect sensor have been connected to my console physically, but the console dashboard keeps showing the sensor is not connected and unplugged error message. If your Xbox one also run into the same issues, please try the the following suggestion from calling support.
* Make sure the sensor is attached to the console securely. The Xbox logo LED shoud be lit.
* If the connected Kinect sensor is not recognized, you need to go to the Kinect settings to turn it on. Once you’ve done, the Xbox logo will indicate that the front of the sensor is lit.
* Reset the connection.
1. Press the Xbox button on the front of the console for about 10 seconds until it shuts down completely.
2. Unplug the console’s power and the Kinect from the Xbox One console.
3. Plug the power back in and Power the Xbox One back up
press the Xbox Button, press the menu button from controller and select Settings > Kinect. Plug in the sensor and it should be recognized after five seconds.
* If the device is still not working at all, you have to do a replacement. Visit myservice.xbox.com and process your sensor for repair.
I have done an exchange through Microsoft and now everything is fine.