Unable To Move Files From Drive

unable to copy files off the drive. There are four files, shot on different days (70, 71, 72 and 73). I can start to move 70 and 71 off the drive, but then it slows down after awhile. Drive sounds "grindey". Files 72 attemps to download but nothing happens. 73 attemps, but the get this error: "can't complete the operation because some of the data can't be read or written (error code - 36). I cannot get the drive now to mount in the KiPro unit