http://www.extremeipod.com/article2/0,1759,1776090,00.aspFor Early iPods(The iPod, iPod with Scroll Wheel and iPod with Touch Wheel):
Turn the Hold switch on, then turn it off again.
Hold down the Play/Pause and Menu buttons until the Apple appears, "around 6 to 10 seconds" according to Apple.
For Later iPods (The iPod with Click Wheel, iPod photo, and iPod mini):
Turn the Hold switch on, then turn it off again.
Hold down the Menu and Select buttons until the Apple appears, again, roughly 6 to 10 seconds.
Didn't work?
Make sure the iPod has power by connecting to your power adapter. Try repeating it a couple times before you give up and starting thinking about restoring your iPod.
Some of your custom settings missing? Sorry about that, but it's pretty normal when you reset your iPod. None of your music or other files will be wiped. (If you run a restore on your iPod, all of them will be wiped!)
Your iPod doesn't work even after a reset? Then it's probably time to try to restore your iPod with the iPod Updater.
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