Share your experience!
was the memory card reformatted properly before you transferred your files?
can you view the files using your phone? file manager?
have you tried using a card reader instead of viewimg it thru your phone mtp?
If the SD card was corrupted there isn't much you could do, you can download RECUVA and try to restore them.
could you try to transfer a new file and see if you experience the same issue?
how did you transferred the files to the SD card?