i'm having a very similar problem... more like several problems and that's one. i formatted a disk, saved two files to it from my word processor, used very little space, overwrote them to check it, and then start having problems formatting other disks. when i tried going back to the one that worked for me, it says it's full. or, in the word processor, it says there's no disk in the drive, and in windows explorer it says there's no disk in the drive. we got the very first try after getting new brands of cdrw's, thinking a media brand would solve the problem, but no. after the successful try we couldn't reproduce the success. very frustrated.