I downloaded some wedding photos into my external drive about a month ago. A total of 3 cards were downloaded into 3 different files. The first file lists all of the photos, about 600 images, but they have zero bytes. The other 2 files are fine. I can't recover the compact flash card because I have used it too many times since then. Is there any way to recover the images on my drive?
Sorry, can't be done.
Zero byte file size means that everything but the file name is gone. And since you have used the flash card several times there is nothing you can do.
You have my sympathies.
In case it happens again make sure you tried Photorec before writing to this disk, even if your filesystem is damaged and don't report a size for files, data can still be here though.
The way Photorec works is by scanning the drive for file headers then following pointers to next blocks then write eache file found in a new file.