What does: _MAG0001.JPG really mean?

i am trying to recover photos from a 256mb cf card.

recuva reports finding multiple images but does not display thumbnails of them.

i check the box under the image to display it and click on it.

rucuva then displays a black box stating invalid image.

i have used the topic title above as an example.

recuva finds about 50 to 75 images and displays them with differing prefix names like _mag0002.jpg / _mag0075.jpg.

ocasionally recuve states that an image is partially recovered but displays the same black box and message.

is there some guidance on what i am seeing here?

is this situation a total loss?

best regards,

mike lynch