Genaudio

Hi All. Just purchased a sony MDS-JE780 to record my live work and transfer to PC with OpenMG. I managed to transfer some music tracks from MD to PC but I have this 41:02min / 85.83Mb ATRAC file marked with a sort of double-leaf sign which when I am trying to check-in, "selected song(s) cannot be checked-in" pops up. Can anybody tell me why? I am VERY new to this MD recording stuff! Thanks to all.