If your HP touchpad is not charging, it may be that you have to reset your plugin i.e. the cylinder that you plug into the wall. To reset it, unplug the cylinder from the outlet, remove the usb cable. You then twist the end of the cylinder with the prongs counter clockwise, then you twist it back to its original position. You don't have to twist it that far until you reach resistance in either direction. There you have just reset your plugin, so plug it in directly to a wall outlet and hopefully you will be able to charge your touchpad. Leave it plugged in for 2 hours to see if it worked.