My Lacie disk isn't showing and I keep getting the "disk not ejected properly"

Help! I have three Lacie disks. Two of them work fine, the other one that contains all of my iPhoto Library (photos and videos) doesn't show on my computer at all and used to. The other drives show up and work like they are supposed to. When I have iPhoto open, I keep getting the "disk not ejected properly", but why am I getting this when the computer doesn't show it's connected? I am in desperate need of getting this drive to not only connect to my computer, but to get all of my photos/videos back! The drive acts like it is working, flashing light, etc., but I can't see it on my computer to access it. When I called Lacie, they had me hook up the drive directly to the computer via USB. Right now all three drives are connected through a lightning bolt that's been working for a long time. When I connected the "bad" drive to my computer via USB, it didn't show on my computer. Lacie is thinking it's a bad drive, but I think my computer doesn't want to accept it or maybe it thinks its connected and that's why its giving me the disk not properly ejected message. Can somebody help me before I go insane?!