The iTunes Restore feature reinstalls the latest version of the iOS, restores all settings to their defaults, and deletes all music, apps, videos, and other data on your device. However, if you've backed up your device, you can restore that backup (including all data and settings) after you've restored the iOS. Restoring your device is recommended if you're still having problems after restoring settings and have restarted or reset your device. Note that you must be able to connect your iOS device to your computer to use the Restore feature. Here's how you use Restore:
- Make sure you have the latest version of iTunes installed on your computer.
- Connect you iOS device to your computer using the USB sync cable.
- Open iTunes on your desktop computer and select your iPhone, iPod touch, or iPad in the Devices list in the left-hand column.
- If your device does not automatically sync, click on the Sync button in the bottom-left corner of the screen. Wait until the iTunes finishes syncing/backing up your settings.
- If not already in the Summary screen, click on the Summary tab at the top of the screen.
- Click on the Restore button in the middle of the screen. (Note: If you did not sync your device upon connection, or if you have delete apps or made changes to your iOS device settings since syncing, iTunes will ask you if you want to back up your settings. Click on Back Up.)
- Click on Restore and confirm it when asked, "Are you sure you want to restore…" (Note: The Software Update Dialog may appear. If it does, click Next> Agree.) iTunes will restore the most recent version of the iOS and the original settings and software.
- At this point, iTunes will present you with the "Restore from the backup of" option. Select the most recent backup from the list and click on Continue. iTunes will restore the backed-up data, restart your iOS device, and sync it.