I changed the icon for a partition on my Macbook's HDD. I opened the Get Info window, and dragged in a .png file I wanted to use. It worked fine. But then I realized I needed to edit the image a bit, but when I dragged in the edited image, I just get this generic PNG icon. I tried putting the original image back, but I just get that same thing again. No matter what I do I'm just stuck with this... I tried repairing permissions, but that didn't help. Ideas?