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Redsn0w - Jailbreak iOS 4.2.1 (iPhone 3G / 3GS / 4, iPad, iPod Touch 2-4G)

Update: iOS 4.2.1

Redsn0w 0.9.6b ../ rc .. -
NOT tethered jailbreak - iPhone 3G, iPhone 3GS (old bootrom), iPod touch 2G (not MC)
Tethered Jailbreak - iPhone 3GS (new bootrom), iPhone 4, iPod Touch (2G (MC), 3G, 4G), iPad

Redsn0w 0.9.7b .. -
* For Mac users only, the presence of saved SHSH 4.2b3 in Cydia is required
NOT tethered jailbreak iPhone 4, iPad and iPod Touch 4

Attention! Unlock iOS 4.2.1 is only possible on iPhone 3G and some iPhone 3GS
After flashing the locked iPhone 3GS (old boot) or iPhone 4 in this way, you will get a BRICK

Installation FAQ and Jailbreak iOS:

Before you begin, read the entire FAQ!

Untethered Jailbreak. iPhone 3G, iPhone 3GS (Old boot), iPod touch 2G (MB)

  • We update iTunes to the latest version, iTunes 10.1 you can download HERE
  • Install iOS 4.2.1 on your iPhone, (preferably set as " NEW ")
  • Getting started with jailbreak using RedSn0w

    • Download Redsn0w 0.9.6rc8 For Windows HERE
    • Download Redsn0w 0.9.6rc8 For Mac HERE

Untethered jailbreak. ( required availability of SHSH 4.2b3 in Cydia, suitable only for iPhone 4, iPad and iPod Touch 4 )
Download Redsn0w 0.9.7b6 For Mac HERE

  • Download the official iOS 4.2.1 via iTunes , or HERE

    iTunes stores downloaded firmware along this path:
    • for Windows XP C: \ Documents and Settings \ Username \ Application Data \ Apple Computer \ iTunes \ iPhone Software Updates
    • for Windows Vista Start \ Username \ AppData \ Roaming \ Apple Computer \ iTunes \ iPhone Software Updates
    • for Windows 7 Start \ username \ AppData \ Roaming \ Apple Computer \ iTunes \ iPhone Software Updates
    • for Mac OSX \ username \ Libraries \ iTunes \ iPhone Software Updates

  • Close iTunes !!!
    Launch RedSnow (run on Win 7 with Administrator rights and compatibility mode with XP SP3 ). Click Browse and select iOS 4.2.1 firmware in the window that opens.
  • Click Next . To continue, Redsn0w recommends turning off the phone (hold the Power button on the phone and drag on the slider that appears).

    Using the checkboxes, select the necessary components:

    • Install Cydia - upload Cydia installer to the device. Without this, a jail loses 90% of its meaning;
    • Verbose boot - text download mode . When you start the device, instead of the bullseye, you will see diagnostic messages on a black background. To the average user (and non-ordinary too) this option is unnecessary;
    • Install iPad baseband - install the modem from the iPad (06.15.00) , which can be unlocked using Ultrasn0w 1.2 ( it will not be possible to return the old modem !!! );
    • Custom boot logo - the ability to replace the bull’s boot when loading on any other picture. When installing a checkmark, a window will immediately appear in which you need to specify a graphic file for replacement (only PNG, preferably 320? 480 and not more than 100KB of weight);
    • Custom recovery logo - the ability to replace the iTunes logo and lace, which are displayed when the device starts in recovery mode, with any other picture. The requirements are the same as for the boot logo;
    • Enable multitasking (the option is visible only for iPhone 3G and iPod Touch 2G) - activation of multitasking at the cost of a strong slowdown of the system;
    • Enable homecreen wallpaper (the option is visible only for iPhone 3G and iPod Touch 2G) - activation of the desktop background image. Also leads to slowdowns;
    • Enable battery percentage (option visible only for iPhone 3G and iPod Touch 2G) - activates the display of battery percentage. Unlike the previous two options, it does not lead to negative consequences (To enable: Settings -> basic -> statistics -> battery charge);
    • Just boot tethered right now - this option is useful only when your device refuses to turn on after rebooting. Selecting this option removes all the upper checkmarks;
    • Just enter pwned DFU mode right now - the option is needed if you just need to enter the device in DFU mode. Selecting this option removes all the upper checkmarks.

    * I DO NOT recommend turning on wallpaper and multitasking on iPhone 3G and iPod Touch 2G (since there are not enough hardware resources for this phone)

  • Click Next ,
    Next, you need to transfer the phone to DFU mode , following the instructions on the screen:
    • Hold the Power button for 3 seconds .
    • Without releasing the Power button, hold down the Home button for 10 seconds .
    • Release the Power button, but continue to hold Home for 30 seconds .
    • After the white screen appears, release both buttons.

  • It remains only to wait a bit (Downloading Jailbreak Data ... appears on the phone screen, then the running "Pineapple", after the jailbreak the phone reboots). If Redsn0w crashes , then simply repeat step 7 .
  • If the Cydia label is displayed in white , then repeat step 5 , in step 6, check only “ Just boot tethered right now , after the jail is complete we get a working version of Cydia .
    Do not forget to go into Cydia and install all the proposed updates:

    • Do not run Cydia while your phone is not connected to the Internet, EDGE or WiFi .
    • Check or configure your Internet connection, and then launch Cydia .
    • The reorganization of Cydia will begin. Wait, after the reorganization of Cydia closes itself, and you will be thrown to the desktop.
    • Launch Cydia again (to the question Who Are You? Answer Hacker (+ Command Line) ) and you will see important updates for Cydia , install them ( Complete Upgrade )

    Tethered jailbreak. iPhone 3GS (New boot), iPod Touch 2G (MC), iPod Touch 3G, iPod Touch 4G, iPhone 4, iPad (in the absence of a Mac and SHSH 4.2b3)

    We use the same instructions as for iPhone 3G, iPhone 3GS (Old boot), iPod touch 2G (MB), only at the output we get Bound Jailbreak.

    “At the moment, you can jailbreak only in a“ tied ”way. This means that every time you disconnect (or completely discharge) the device, you will have to connect it to a computer with Redsn0w installed and go through the whole hacking procedure again (leaving only one option “ Just boot tethered right now " ). Otherwise, iDevice will not succeed."

    Untethered Jailbreak. iPhone 4, iPod Touch 4G, iPad ( only if you have a Mac-computer and saved SHSH 4.2b3! ) This untethered jailbreak uses ECID certificate or SHSH blobs 4.2b3 (iOS 4.2 beta 3). To check for SHSH blobs from the third beta version of iOS 4.2, launch Cydia and wait until the main page loads. “ SHSH: 4.2b3 " should appear on the screen.
    We use the same instructions as for iPhone 3G, iPhone 3GS (Old boot), iPod touch 2G (MB) only for a place Redsn0w 0.9.6 we use Redsn0w 0.9.7b6 :

    Download Redsn0w 0.9.7b6 For Mac HERE

    Attention! In point 5, after specifying the iOS 4.2.1 firmware, click Next, then select the Jailbreak Monte option and specify the iOS 4.2 Beta 3 firmware file

    For acceleration firmware 4.0.1 - 4.2.1 works on iPhone 3G and iPod Touch 2G recommended:
    • disable wallpaper
    • disable multitasking
    • disable Spotlight search (settings - basic - home button - Spotlight search - uncheck all and reboot)
    • From time to time, restart the phone by holding the Home and Power buttons for 10 seconds until the phone turns off

    Turn on / off wallpaper and / or multitasking. (Actual for iPhone 3G)
    Install the zToggle application from the BiggBoss repository in Cydia .

    File manager with support for updated iTunes iFunBox

    All your actions with the phone, you do at your own peril and risk!

    To be able to have an untethered Jailbreak in future firmware
    I recommend to keep SHSH certificates !!!

    Frequently asked Questions:

    If Redsn0w hangs on the message “ Uploading ramdisk ” and the message “ downloading jailbreak data ” lights up on the phone screen and nothing happens for more than 5 minutes

    • Run the Redsn0w file on behalf of the Administrator and in compatibility mode with XP SP2 / 3 .
    • The firmware file may not be fully downloaded. Download the .ipsw firmware file again or from an alternative source.
    • Redsn0w may freeze on some configurations due to the use of multi-core processors. Open the " Task Manager ", in the " processes " find " Redsn0w.exe ", in the context menu select " Set compliance ... / SetAffinity ", leave the checkmark only on " CPU0 / CPU0 ".

    Having an iPhone 4 and a Mac computer, is it possible to save the SHSH certificate by firmware on iOS 4.2b3, for further use of the untethered jailbreak?

    • Not! Subscription to SHSH certificates below iOS 4.2.1 is already closed.

    When will the full Jale come out? When to wait for a jail under windows?

    • Follow the news on the website and forum, as soon as a new solution appears, you will be the first to know about it.

    After flashing the device and installing all the updates in Cydia, it stopped starting, Safari also does not work

    • Follow the 9th point of the instruction
    • Flash the device again, strictly following the instructions

    During the firmware process in iTunes, xxxx error appeared

    After the jailbreak and reboot of your device, a white apple is lit on the screen.

    • Most likely, your device does not support untethered jailbreak.
      Each time you disconnect (or completely discharge) the device, you will have to connect it to the computer with Redsn0w installed and go through the entire hacking procedure again (leaving only one option “ Just boot tethered right now ”)

    How to find out BootRoom version of my iPhone 3GS?

    • By device serial number ( Settings -> General -> About device )
      Example: 87022Z635NQ
      We are interested in the 3rd, 4th and 5th digits:
      xx 022 xxxxxx
      3rd digit year (" 9 " -2009, " 0 " -2010)
      4.5 digits week - until the 40th week of 2009 BootRoom old
      Above the 41st week of 2009 or the whole of 2010, BootRoom is new !
      If you have a border week (40-41) it is better to use the program described below.
    • Using iDetector

      • download iDetector
      • if Java is not installed, then go to, download and install the latest version
      • we transfer the phone to DFU mode (7th paragraph of the instruction)
      • run iDetector, click on the button, find out the bootrom version
      • to exit DFU again hold Home + power button.

    Is it possible to lower the modem version by downgrade firmware (SHSH saved)?

    • No, the modem version does not go down!

    How can I flash a locked 3G / 3GS phone on iOS 4.1-4.2.1 with an iPad modem (06.15.00)?

    • The modem version 06.15.00 has a version higher than any of the modems of all currently released 3G and 3GS phone firmware, and therefore updating the phones with factory firmware via iTunes on your phone will fail with error number 1015 , and the phone will remain in recovery ( recovery ) mode ) from which it will not be so easy to pull it out.
      And so you already have the modem installed 06.15.00, the phone is jailbroken and you want to restore the firmware, for this we follow these simple steps:

      • A ) if you use the PwnageTool utility to jailbreak, then use this utility to create custom firmware version 4.1 or 4.2.1 , when the program asks you to install BB (modem) on 06.15.00, you should refuse this. Finish creating custom firmware and flashing your phone using iTunes .
      • B ) if you use RedSn0w , then you have two options:
        • B-1 ) if you already have firmware 4.1 , then flash 4.1 again, and when the window with error No. 1015 appears on the screen, launch Tiny Unbrella and remove the phone from the " recovery " mode (recovery mode). After that, start Redsn0w , follow its instructions, and when you get to a lot of checkboxes, DO NOT NOTE the installation of the 06.15.00 modem, because you already have it.
        • B-2 ) if you already have 4.2.1 , then you need to flash 4.1 (because 4.2.1 will not allow you to remove the phone from the " recovery " mode, because a silly check for modem / OS compliance has already been added to it , i.e., for example, for iPhone 3G, iOS 4.2.1, the modem should be 05.15.02 and no other), well, then follow the instructions from paragraph B-1 . If you want to flash firmware 4.2.1 , then you have only one way out - to create custom firmware according to the instructions of point A , there are no other ways at the moment.