Trying to securely erase hard drive, but Security Options not available (Mavericks) Recently got a new Macbook Pro 13″ and I'm preparing my old Macbook Air for sale. I'm following steps in the Apple Support article on this topic (as well as other similar articles I've found).

I'm currently at the stage of Erasing the startup disk. I've booted my machine with ⌘R and am running Disk Utility. Initially I was able to set Security Options to Most Secure (7 pass zeros), but after I clicked Erase there was some error and it said it could not be completed.

Now Security Options is grayed out (unavailable), however Erase is still available.

The error occurred after only seconds, so I'm assuming it did not actually complete a 7 pass erase and rewrite before stopping. Guessing that means my data is still there and relatively accessible.

Is there anyway to re-access the Security Options and get this thing to securely wipe from this point?
Yes, it is possible to re-enable secure erase. All you need to do is to format the partition once again. Just make sure you select "Mac OS Extended (Journaled, Encrypted)", with any password that you will remember (just in case). Once formatted, the "Security Options" button will be available again, and you can securely wipe out the partition!