harddrive

I have problem storing images on the harddrive. I had somebody look at it and they suggested to defragment the harddrive. We defragmented the harddrive for 48 hours and also deleted old data. The capacity is 140 gb, and there is only 28gb used, but still it comes the red light that it is almost full. We had somebody look at it and they suggested to change the harddrive. But we are not sure how to get the software. Please suggest what we should do to get the Phillips hd9 software for ob/gyn 3d/4d ultrasound machine harddrive.