I really don't know NTFS or FAT32. I'm just a 67 yr old woman who has been enjoying my computer since 1997, but never got into technical stuff. I just go through life documenting everything onto my computer and taking hundreds, sometimes thousands, of photos every month. I am on my computer every day for hours. I back stuff up to my external 5TB hard drive now and then, but now I know it has to be more often. That's why I panicked when I accidentally deleted so much important data. It never happened before, and truthfully I still don't understand how it happened since I basically do know what I am doing when I delete files. I had highlighted a few folders within the big folder, yet the entire big folder disappeared. I don't understand it and probably never will. I didn't count how many of the empty boxes there were in the recovered jpgs. Recuva recovered about 3,000 jpgs, so it would have been difficult to count. They had all been jpgs marked "excellent", all had the green button. There were more good jpgs than empty ones, but I just wondered about those empty ones. All in all I am very pleased with Recuva and I am glad it was recommended to me and I will recommend it to others. And I thank you for all your info. It's nice to know there are people who care enough to try to help.