Apple recently released iOS 4.2.1 for the iPhone, iPod Touch and iPad. There is a jailbreak available for iOS 4.2.1 too. However, at times, your iDevice could throw problems, which is why it is a good option to backup your SHSH blobs.
However, if you are having problems with your iPhone, iPod Touch or iPad after upgrading to iOS 4.2.1 or jailbreaking your device, you can downgrade your device to an earlier version.
If you don’t plan to downgrade your device, you might still have to restore it to an original firmware. If you are having trouble with iTunes, you can download the iOS 4.2.1 firmware directly from Apple. You will find the links to download the iOS 4.2.1 firmware below.
- Download IPSW for iPhone 3G
- Download IPSW for iPhone 3GS
- Download IPSW for iPhone 4
- Download IPSW for iPod Touch 2G
- Download IPSW for iPod Touch 3G
- Download IPSW for iPod Touch 4G
- Download IPSW for iPad
Once you download the IPSW file, you will be able to restore your iPhone, iPod Touch or iPad to iOS 4.2.1.