I have several Canon cameras and recently ran into a problem downloading. I shot senior pictures and when I downloaded the files, about 10 files in the middle of the series were not transferred. I had not formatted the card, so I was able to run some recovery software and the pictures were there. I thought at first it was a unique situation, but it happened again with a different flash card a few days later. images before and after the missing ones were there and numberred correctly, but the missing ones were not there although the numbers were used. Anybody else run into this.