Hi so I have a seagate hard drive and I recently transferred a lot of pictures from my Mac to it. Then when it was done I unplugged it and wrapped the cords up. Now about 2 weeks after this I tried plugging it into my other computer and it won't turn on. I've tried two of the same power cords and it still won't turn on. Please help I have a lot of valuable stuff on there. Also what could have cause this to happen?