toxicredlilies

i bought an ohm usb 2.0 compact sdhc multi-card reader today from target for $6 because i want to transfer some of my photo and video files back onto my memory card so that i can view them on my digital camera.

i got it home and plugged it in to the usb port and dragged and dropped all the files that i want into the folder, but when i take the memory card out of the reader and put it in my camera, my camera says that there are no files found. but when i put the memory card back in the reader and plug it into my computer, all the files are there still. the files i want to be on my camera also show up when i plug the reader into a laptop. i tried two different memory cards. The files that were already on the card still show up on my camera. (i've been using these memory cards in my camera for over a year and they always work)

why won't the files show up on my camera?

memory card reader: ohm usb 2.0 compact sdhc multi-card reader sd/mmc/rs-mmc compatible
digital camera: casio elixim 8.1 mp
memory cards: a lexar sdhc 4gb and a lexar sd 2gb