User Guide

Passcode Lock
By default, iPhone doesn’t require you to enter a passcode to unlock it.
On iPhone 3GS or later, setting a passcode enables data protection. See “Security
Features” on page 54.
Important: On iPhone 3GS, you must also restore iOS software to enable data
protection. See “Restoring iPhone” on page 257.
Set a passcode: Choose General > Passcode Lock and enter a 4-digit passcode, then
enter the passcode again to verify it. iPhone then requires you to enter the passcode
to unlock it or to display the passcode lock settings.
Turn passcode lock o: Choose General > Passcode Lock, enter your passcode, and
tap Turn Passcode O, then enter your passcode again.
Change the passcode: Choose General > Passcode Lock, enter your passcode,
and tap Change Passcode. Enter your passcode again, then enter and reenter your
new passcode.
If you forget your passcode, you must restore the iPhone software. See “Updating and
Restoring iPhone Software” on page 256.
Set how long before your passcode is required: Choose General > Passcode Lock and
enter your passcode. Tap Require Passcode, then select how long iPhone can be locked
before you need to enter a passcode to unlock it.
Turn Simple Passcode on or o: Choose General > Passcode Lock, then turn Simple
Passcode on or o.
A simple passcode is a four-digit number. To increase security, turn o Simple Passcode
and use a longer passcode with a combination of numbers, letters, punctuation, and
special characters.
Turn Voice Dial on or o (iPhone 3GS or later): Choose General > Passcode Lock, then
turn Voice Dial on or o.
Erase data after ten failed passcode attempts: Choose General > Passcode Lock,
enter your passcode, and tap Erase Data to turn it on.
After ten failed passcode attempts, your settings are reset to their defaults and all your
information and media are erased:
 On iPhone 3GS or later: by removing the encryption key to the data (which is
encrypted using 256-bit AES encryption)
 On iPhone 3G: by overwriting the data
Important: You can’t use iPhone while data is being overwritten. This can take up to
two hours or more, depending on the model and storage capacity of your iPhone. (On
iPhone 3GS or later, the encryption key is removed immediately.)
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Chapter 25 Settings