Erase disk
I am trying to erase the disk on my old mac but it says "this operation cannot be performed because you cannot unmount the volume you are booted from". What do I need to do?
Question marked as
Restart with the Command and R keys held down. If the computer's model or firmware is too old for that to be available, insert a Mac OS X install DVD or thumbdrive and restart with C or Option held down.
(199511)