Ask Jacob
How do I use rewritable CDs and DVDs on a Mac?
Wednesday, May 9, 2007 / Hardware
I bought some DVD-RW (Memorex) to use for backing up a freelance project I work on. I thought by buying rewrites, that I would reuse them instead of wasting all those CDs. But when I went to write over it, it says the disk is full, when I try to move a file to the trash it tells me I don’t have privileges. I’m working in the administrators account on my Mac every time. The DVDs came with no instruction for rewriting. Is there something obvious I’m missing?
It’s certainly not intuitive, but you have to use Disk Utility to erase CD-RW and DVD-RW media. For years people have been complaining about this and Apple has never changed it. Using rewritable media this way is a pain and very un-Apple-like, but this is how you have to do it unless you buy additional software. To erase that DVD-RW, put the disc into your drive and open the Disk Utility application. Click once on the DVD-RW in the leftmost window pane of Disk Utility. Click Erase and select "Quick Erase." Then you should be able to write over your disc.
I am not a big fan of rewritable media. They have a limit to how many times you can rewrite them and they are prone to failure, just like floppy disks. I prefer CD-R/DVD-R backups because they are dated backups of my files. Their one time use forces me to have multiple copies of the same file. Sometimes it is an older copy, but if I have just lost a project file I will settle for an old copy over no copy any day.
