I place a lot of photos on CD-R disks & am not sure if I'm doing it correctly. I format the disk in Mastered format. I then drag photos off of desktop, place on the new disk, close session & eject. Every once in a while, I'll place a disk in the computer & it just goes round & round in there & won't be recognized even though it worked fine just the night before. I will then place another disk in the drive & that works fine. Am I doing something wrong? Is "close session" equivalent to burning or as safe saving items on disk? Are the disks faulty even though they're new? Thank you for any help you can give me.