I have Sony's External DRX500ULX DVD burner and can't read the files in each directory on the Mac. I have the Sony on a Windows XP system and used a DVD-R. The Mac is a 17" Power Book with a Super Drive DVD burner running OS X. The file structure on the DVD shows up on the Mac, but each directory is empty. I can copy the same info to a Zip disk or CD ROM with no problem accessing the files. I can put the same DVD disk back in the Sony DRX5000ULX and access it on the Mac through the network and access each file on the Mac with no problem. Something about the DVD when it is in the Mac. Any ideas?