Hey, I'm new. I just bought a new MyBook HDD and hooked it up to my MacBook Pro. I'm mainly using it for storing videos that I upload into iMovie. The only problem I have is that when uploading a video, my MyBook HDD doesn't show up on the drives to save to. So Ive been stuck uploading the videos to my internal HDD and its now full. I'm not sure what to do. The HDD shows up in the finder, and I can more stuff onto the drive but its not working with iMovie. Please Help me.