This at least protects your personal files from a thief - they’ll just have to start over from scratch. RELATED: How to Wipe Your Mac and Reinstall macOS from ScratchĮven if your Mac is securely encrypted, anyone with access to it - for example, a thief who stole your MacBook - could enter recovery mode and use the “Reinstall OS X” option to wipe your entire hard drive. These same tools are available by booting from OS X installation media - a DVD or USB drive - on a Mac. This would allow anyone with access to your Mac the ability to change your password and access your user account, although FileVault encryption can protect against it.
Traditionally, it’s been possible to boot into recovery mode and select Utilities > Password Reset from the menu, which you could use to reset a password if you’ve forgotten it. This option was removed back in OS X Lion, but you can still access the same password-reset utility in recovery mode by selecting Utilities > Terminal, typing resetpassword into the terminal window, and pressing Enter.
Recovery Mode doesn’t normally require a password to access, even though you’d need to enter your password when booting your Mac normally. The key to this process is Recovery Mode - a special environment anyone can access on your Mac if they reboot it and hold Command+R as it boots up. RELATED: How to Bypass and Reset the Password on Every Operating System
