Disk Security: How To Encrypt Your Mac With FileVault
If you want to sell or replace your Mac, it is only normal to want to wipe it out first. No one wants their personal information and files to be available to the next user. Today, it is possible to sell an old, used and even broken Mac online, so it may very well be that you’ll need to erase data on your computer. Encrypting your Mac is also highly recommended even if you plan to keep your Mac. Encryption makes your files unreadable to an unauthorized party and thus adds security.
To encrypt a drive on Mac is very simple with the built in FileVault system. Thus, to encrypt your Mac simply go into Settings then Security and Privacy and then turn on FileVault. Depending on the size of your disk and the amount of data on it, encryption make take anywhere between minutes to hours. The computer will give you two options, to set a recovery key or to unlock the data using your iCloud account. If not, you could use all your data (if you forget the password you set).
Alternatively, you could also erase your drive. With the new El Captain system upgrade you can no longer erase your data using the secure trash option. That’s why the secure data erase through the erase data trash has disappeared. No longer the secure data erase is guaranteed.
However, to erase the data once and for all, first you need to open your System Preferences. Then go to Security and Privacy, start the Mac OS Disk Utility, then choose erase disk and choose the disk you want to erase. A pop up window will ask if you really want to erase all the data, click yes and you’re good to go. Repeat the steps to make sure data is fully erased. You want to repeat the steps to make sure the data is truly and safely erased.