If your Mac is stolen, could someone read your files?

Why it happens

FileVault locks the whole startup disk behind your login password. A thief can't get at your files by guessing around the login, starting the Mac another way or connecting it to another computer. The one catch is that you need your password or recovery key too: if you lose both, your files are gone for good.

How to fix it

1. Choose Apple menu > System Settings and click Privacy & Security in the sidebar.

2. Scroll down to Security and look at FileVault. If it says FileVault is turned on for your disk, your files are already protected. The tips further down make a stolen Mac even less useful to a thief.

   Privacy & Security›FileVault

3. If it's off, click Turn On… and enter an administrator's password. Your Mac carries on working normally while it finishes.

4. Choose how you'll get back in if you ever forget your password: your iCloud account, or a recovery key. If you pick a key, write it down and keep it somewhere other than this Mac, such as a printed copy at home.

Still not fixed?

1. Turn on Find My Mac, so you can see where a lost or stolen Mac is, lock it and erase it from another device. It also adds Activation Lock, which stops a thief setting the Mac up as their own.

   Apple Account›iCloud›See All›Find My Mac

2. Make sure the screen locks when you step away. In Lock Screen, set Require password after screen saver begins or display is turned off to Immediately or a short time.

   Lock Screen›Require password after screen saver begins or display is turned off

3. Add a way for an honest finder to reach you. Turn on Show message when locked and type a phone number or email address.

   Lock Screen›Show message when locked

4. Keep a recent backup with Time Machine or iCloud Drive. FileVault keeps your files private, but only a backup gives them back if the Mac is gone.

5. If FileVault won't turn on, the button is greyed out on an administrator account, or it seems stuck, contact Apple Support. If your Mac has been stolen, use Find My to mark it as lost and report it to the police.