In Mac OS X, how do I password-protect my computer?

Because Mac OS X is based on Unix, the operating system has native support for a password-protected multiple-user environment. By default, you are required to set a single user with a password. If you have only one user created, your computer will not prompt for a user password when your computer starts. However, you may secure your computer with a password as follows:

1. From the Apple menu, select System Preferences... .
   
   
2. From the View menu, select Accounts (10.2.x and later) or Login (10.1.x and earlier).
   
   
3. In Mac OS X 10.5.x, at the bottom of the left panel, click Login Options. In the right panel next to "Automatic login:", select Disabled from the pull-down menu. If the Login Options are grayed out, click the padlock icon in the bottom of the preference window and authenticate to your account.

   In Mac OS X 10.3.x and 10.4.x, at the bottom of the left panel, click Login Options, and in the right panel, uncheck the box next to Automatically log in as: . If the Login Options are grayed out, click the padlock icon in the bottom of the preference window and authenticate to your account.

   In Mac OS X 10.2.x, click the Users tab, and uncheck the box next to Log in automatically as name, where name is the name you gave your account.

   In OS X 10.1.x and earlier, click the Login Window tab, and uncheck the box next to Automatically log in.

When starting your computer, you will have to authenticate to access your account. You may also log out of your computer without restarting. From the Apple menu, select Log out... .

Locking your screen

Mac OS X also allows you to lock your screen when the screen saver becomes active. You will then have to enter your password to regain access to your computer. To activate this feature, follow the appropriate instructions:

Mac OS X 10.3 and later

1. From the Apple menu, select System Preferences... .
   
   
2. From the View menu, select Security.
   
   
3. Check the box next to Require password to wake this computer from sleep or screen saver.

To add an item to your menu bar that will allow you to quickly lock the screen and turn on the screen saver, follow these steps:

1. From your Applications folder, open your Utilities folder, and then open Keychain Access.
   
   
2. In 10.4 and 10.5, from the Keychain Access menu, select Preferences... . Under the General tab, check the box next to Show Status in Menu Bar.

   In 10.3, from the View menu, select Show Status in Menu Bar to check it.

3. The padlock icon will appear in your menu bar in the upper right corner of your screen. To lock your screen, click this icon, and from the menu that appears, select Lock Screen.

Mac OS X 10.2.x and earlier

1. From the Apple menu, select System Preferences... .
   
   
2. From the View menu, select Screen Effects (10.2.x) or Screen Saver (10.1.x and earlier).
   
   
3. Click the Activation tab.
   
   
4. Under "Password to use when waking the screen effect:", select Use my user account password.

Also see:

• In Mac OS or Mac OS X, how do I make a copy of a file, application, or folder?
• In Mac OS X, how can I take a picture of the screen?
• In Mac OS X, how do I create and delete users?