You will need
  • - ipsw-firmware
  • program Apple iTunes
Instruction
1
System restore will bring iOS to the original "shop" meant. You get a completely clean, validating the phone to factory settings. All uploaded media files, be it games, music or photos will be removed.
Initially, make sure your phone has passed the PCT (Rostest), or neverlost. Neverlost assigned some iPhone imported from USA or European countries. Built-in neverlost will allow the phone to work with SIM card of any Russian mobile operator after recovery.
2
If the phone was purchased in Russia and has no neverlose, there is a high probability that after the restoration it will not ring. In the end, instead of the iPhone you get iPod Touch fully working, but without GSM-connection. On some series it is treated unlock – unlocking GSM chip. But some phones cannot be repaired. So restore your iPhone, you purchased abroad, you are at your own risk.
3
Download the version of the iOS operating system, which you will recover. iOS presented in a single file distribution with the extension *.ipsw. Links to all the existing firmware for iPhone 2G, 3G, 3GS and 4 located here: http://www.apple-iphone.ru/forum/viewtopic.php?f=10&t=5135.
4
Once the firmware is downloaded, run Apple iTunes on your PC or Mac. If your computer does not have iTunes, download the latest version on the manufacturer's website: http://www.apple.com/ru/itunes/download/.
5
Via USB cable connect your iPhone to a USB 2.0 port on your computer and wait until the sync with iTunes library.Then hold down the Shift key on the keyboard and Restore button on the summary tab in iTunes.
You will be presented with an Explorer window in which you need to find previously downloaded ipsw-file with the operating system. Click on the selected file twice with the left mouse button.
6
On the screen bar will show the level of extraction of the software, by filling in which will begin the restoration of the machine. During recovery, do not disconnect the USB cable from your phone or computer. Once the process is complete the screen will display the message about successful recovery. Now you can activate your iPhone.