Hi All" Trying to securely erase the freespace on my macbook's internal hard drive. I do it monthly. and it has always worked. Now when I enter 'diskutil secure erase freespace 3 /dev/disk0s2' in terminal, it gives me the following error: "Erasing freespace only works with a drive that is mounted and writable." It says this regardless of whether the drive actually is mounted and writable. I've tried logging out and erasing the freespace in terminal from recovery mode, and I get the same error despite disk utility saying that the drive is mounted and writable. I've tried from safe mode for the same result. I even tried in single-user mode, and of course the diskutil framework does not work in that situation in general. I've googled this question for hours. Nothing. I've tried manually mounting the hard drive using 'mount -rw /' and fsck, and it says the drive mounted successfully. I've tried using 'diskutil mountDisk /dev/disk0s2' and it says the volume was mounted successfully. The drive is mounted and writable, but the secure erase function off diskutil seems to believe to the contrary. Where am I going wrong?