Check the USB port that you connect to your computer with. Look for bent pins or something lodged in the port . If there is something in the port use a toothpick or plastic pic to remove don't use anything metal . If this brings no joy , is there a card reader or a sd card in the machine , if so take out any card that may be in the tablet . If there is no card in check the slots for debris and clean them . If you get no joy from this remove the battery . Open the case and disconnect the battery . If the battery is soldered to the board then remove the soldered ground only for a few minutes then resolder . Hope this helps