The iPod Touch has a passlock feature that protects your device from unauthorised access by asking for a passcode, which prevents others from viewing the home screen without the correct password. After several failed passcode entries, the iPod Touch temporarily disables itself as an additional layer of security. While this feature is useful if you lose your iPod touch, it can be a nuisance if you happen to forget the passcode. Luckily, a disabled iPod Touch can be re-activated by connecting it to your primary computer used to synchronise information to it and unlocked.
Attach the dock connector end into the bottom of the iPod Touch, and attach the opposite end to the USB port on your computer.
Start iTunes by double-clicking the program's icon on your desktop, and click the iPod Touch's name in the source pane (side window) in iTunes. The device synchronises with iTunes and backs up your device's data.
Push the Home button on the iPod Touch after the device finishes backing up to access your home screen.
Click "Controls" and "Eject iPod Touch" from the iTunes menu to disconnect the device. If you are still unable to remember the passcode, leave the iPod Touch plugged into the computer, click "File" and "Back up" on the iTunes menu, and click "Restore" in the Summary section in iTunes.
Right-click the iPod Touch's name in iTunes, and click "Restore from backup." Click the last backup date to restore your iPod Touch to its previous state before restoring, which eliminates the passcode protection.