DVD question [again]

Sorry for stirring this topic again, but I have another question. There seems to be a difference between "dual layer" and "double layer." Reason I suspect this, is because I bought a Verbatim "Double Layer" 8.5GB DVD and copied the 9.2 Pro DVD onto it. Unforunately my normal DVD-ROM, and no other DVD-ROM I tried. It does work on a few DVD writers though. Thanks -- Kind regards Hans du Plooy SagacIT (Pty) Ltd hansdp at sagacit dot com