I am new to mac and am trying to bring over lots of photographs from a number of old laptops, and PC desktop. I copied a number of photography folders onto a seagate external hard drive. The HD was formatted for PC NTFS. I then split off the remainder of the hard drive into an ex-fat partition. I have been using Adobe Lightroom to move photos to the ex-fat partition. The ex-fat partition is very unstable. Whenever I shut the lid all the partitions close and won't reopen until I restart the whole computer. Sometimes after restarting the ex-fat partition takes a very long time to mount. I am not sure of how long but I don't think its going to happen and then notice it's in my finder later. How can I make this external hard drive more stable or reliable?