Edited Photo appears black when saved to my Apple Desktop

After I have completed my editing in Elements, I save my results to my Apple Desktop. The thumbnail sketch of the photo is solid black, not the actual picture. When any  jpg is saved to my Desktop you normally see the picture and not just a black square. When you click on the black thumbnail photo, you do get the enlarged photo as you would see it in Elements. The problem is that if you import the photo into Apple Photos, the thumbnails are all black until you enlarge them. How can you avoid the photos being stored as black?