DVD-R disks can be written to only once. They are not reusable.
DVD-RWs can be written to multiple times. After about five times, though, data written to it tends to become more and more corrupted. If this is the type of DVD you want to use, you should first use Windows DVD Maker to erase it, then treat it like a normal blank disk. [ theymos's advice column | Ask theymos A Question ]
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