This is just a wild guess. I burned one file compilation to DVD just fine, then created another one and it started getting getting RESULT 0x80040255 solid. The project indicated I had about 9MB remaining on the disc but I noticed subsequent attempts to re-burn the same disc did not prompt me to erase the disc. Hmm, I said. Is it even hitting the disc before failing, I wondered? Just for laughs I deleted one randomly chosen directory containing about 38MB from the project. Now it's burning and has completed. Perhaps the project size was too large even though CDB said it should fit???