I had this external hard drive for 6 months now. Today I was using my computer like usual with the hard drive plugged in when suddenly it shows a dialog saying that my external hard drive has been incorrectly removed. I haven't been able to use my hard drive since. When I plug it in, there's no running noise, the hard drive doesn't show up on the desktop or in the disk utilities. The LED activity light on the hard drive is out too. Please help, lots of important data on it.