Upgrading to the new iOS6 might be an exciting time for Apple users, but a failed upgrade can mean massive data loss if you do not have a backup made. To avoid data loss and corruption, there is a way to safely make a backup before you upgrade and store it on your computer.
Before an iOS upgrade, the system automatically takes a backup for you and proceeds to erase the data you already had. This might come in handy, but unfortunately the process is not fail-safe: if there is a power failure during the upgrade or there is a difference between iOS versions, you might lose some of your data, and the backup you have will become corrupt.
Backup corruption is a serious issue, and Apple fans should be advised: this is what happens when your backup becomes corrupt.
We strongly recommend that you make a copy of your backup and store it safely before upgrading. The backup contains all your contacts, text messages, calendar, notes, call history and app data.
You can either create a backup using iTunes or iCloud. To backup with iTunes, connect your device to a computer with the latest version of iTunes, select your device under Devices and right-click (or CTRL-click) and select 'Back Up'. Backing up with iCloud is much easier – just enable the option on your device by going to Settings > iCloud > Backup & Storage. Note that if you turn on iCloud backups, your iTunes backup will be turned off.
The iPad/iPhone backups you make are stored in different folders, depending on which operating system your computer is using. The default backup location is the same between iOS and iDevice, whether you have an iPhone or iPad and whether you have an iPhone with iOS 5 or iOS 6 installed.
Once you know this, you can go to the default folder, make a copy of your backup and store it somewhere safe so you don’t lose your data, then you can safely proceed with the upgrade to iOS6. If anything goes wrong with the upgrade, you can just reset your device and restore with the copy of the backup. We also have a guide on how to restore from an iTunes backup.
Remember, when you want to upgrade, don't connect it to iTunes. If you connect your iPhone to iTunes and let it sync, it may well take a new backup and overwrite your old one. If your old backup gets overwritten, the iPhone Backup Extractor probably won't be able to find your data.
Where does iTunes store its backups?
Windows XP: \Documents and Settings\USERNAME\Application Data\Apple Computer\MobileSync\Backup
Windows 7: \Users\USERNAME\AppData\Roaming\Apple Computer\MobileSync\Backup
Windows Vista: \Users\USERNAME\AppData\Roaming\Apple Computer\MobileSync\Backup
Mac OS X: /Users/USERNAME/Library/Application Support/MobileSync/Backup