If it isn't empty, you won't be able to burn it. A dvd-r can only be written once. If there is already something on the disc, you can't write anything else to it. You would need a dvd-rw (rewriteable) to do that. If you have another dvd-r that has nothing on it, you can write to it. Problem is, you didn't mention if you have a pc or a mac, or what kind of files you want to write to it. Ie; movie, pictures, etc. You need to provide more information. Sorry I couldnt help more.