Please help!! I have a 7inch MID wm8650 tablet .. I useed a male to mlae usb cable to connect it to my pc to copy some file to it.. The pc did not see the tablet .. I shut down my tablet then I pluged out the usb cable.. then when I tried to start the tablet again I found that it can not be started..no green indicator.. nothing on the screen !! Please help ! what can I do ?! Thank you very much..