Hello, I received a HP Simple Save external HD for Christmas a couple of years ago and it worked fine with my Macbook until recently. I don't recall doing anything different than before, but now every time I plug it in, my Macbook doesn't recognize the HD. I went to disk utility and it won't even allow me to use first aid, but my computer recognizes it there...not anywhere else. I haven't tried plugging my HD into a PC since I've been adding stuff to it...don't know if that makes a difference, but just saying. If anyone could please help me, I would greatly appreciate it. Thanks!