The handy Screen Lock feature on Fifth Generation iPod and iPod nano helps prevent others from snooping through your iPod and screwing around with it without your permission.
If you've got a Fifth Generation iPod (iPod with video) or iPod nano, you can lock your iPod screen using a 4-digit combination to keep prying eyes from digging through your iPod contents—including your music, photos, and notes—and using your player without your permission.
Note: Screen Lock only prevents snoops from viewing contents or using your iPod when locked and away from all computers. If you connect a locked iPod to a computer, you'll be able to see all songs on it in iTunes (as you normally would), and access any content on its disk (if you set it up for hard disk use) while it's still locked.
Once your iPod is locked, it won't display its contents onscreen, nor will it be usable until you enter the 4-digit code to unlock it—just enter the code in the same manner as you did when you set the combination. If you enter the wrong code, the numbers will flash red. When you enter the correct combination, you'll have full access to your iPod again. Alternatively, you can connect your iPod to the primary computer you use it with (the one to which you first connected your iPod), and your iPod will unlock automatically.
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