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A full (untethered) jail iOS 4.2.1 for iPhone 4, iPhone 3GS, iPod touch 3G, iPod touch 4G and iPad - Greenpois0n

iOS 4.2.1

A full (untethered) jail iOS 4.2.1 for iPhone 4, iPhone 3GS, iPod touch 3G, iPod touch 4G and iPad - Greenpois0n

Download iOS 4.2.1: HERE

Attention! Unlock iOS 4.2.1 is only possible on iPhone 3G and some iPhone 3GS
Having thus stashed the iPhone 3GS (old boot + iOS4.2.1) or iPhone 4, get the BRICK

Installation FAQ and Jailbreak iOS:
Before proceeding, read the entire FAQ!

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

  • Updating iTunes to the latest version, iTunes 10.1 can be downloaded HERE
  • Install iOS 4.2.1 on your iPhone, (preferably set as " NEW ")
  • We begin jailbreak with RedSn0w

    How to download from Picture FILE EXCHANGERS

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

  • Download the official iOS 4.2.1 via iTunes , or HERE

    iTunes stores the 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 !!!
    Run RedSnow (on Win 7 run with Administrator rights and compatibility mode with XP SP3 ). Click Browse and in the window that opens select iOS 4.2.1 firmware
  • Click Next . To continue Redsn0w recommends to turn off the phone (hold the Power button on the phone and conduct on the appeared slider).

    Use the checkboxes to select the required components:

    • Install Cydia - Fill in the Cydia installer device. Without this, the Jail loses 90% of its meaning;
    • Verbose boot - text mode of loading . When you start the device instead of an apple, you will see diagnostic messages on a black background. For an ordinary user (and even for a non-regular user) this option is unnecessary;
    • Install iPad baseband - installation of a modem from the iPad (06.15.00) , which can be unlocked using Ultrasn0w 1.2 (the old modem can not be returned !!! );
    • Custom boot logo - the ability to replace the bullseye when uploaded to any other image. When installing a checkmark, a window appears immediately in which you need to specify a graphic file to be replaced (only PNG, preferably 320-480 and not more than 100KB of weight);
    • Custom recovery logo - the ability to replace the iTunes logo and the lanyard, which are displayed when the device starts in recovery mode, on any other picture. Requirements are the same as for boot logo;
    • Enable multitasking (the option is visible only for iPhone 3G and iPod Touch 2G) - activation of multitasking at the price of a strong braking system;
    • Enable homecreen wallpaper (option is visible only for iPhone 3G and iPod Touch 2G) - activation of background images of desktops. It also leads to slowdowns;
    • Enable battery percentage (the option is only visible for iPhone 3G and iPod Touch 2G) - activates the display of the battery charge in percent. Unlike the previous two options, it does not lead to negative consequences (To enable: Settings -> basic -> statistics -> battery charge);
    • Just boot tethered right now - the option is useful only when your device refuses to turn on after reboot. Selecting this option removes all the upper checkboxes;
    • Just enter pwned DFU mode right now - this option is needed if you just need to enter the device into DFU mode. Selecting this option removes all the upper checkboxes.

    * Include wallpaper and multitasking on the iPhone 3G and iPod Touch 2G NOT recommend (because it lacks the hardware resources of 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, press the Home button for 10 seconds .
    • Let's release the Power button, but continue to keep Home 30 seconds .
    • After the appearance of the white screen, release both buttons.

  • It remains only to wait a little (on the phone screen appears the message Downloading Jailbreak Data ..., then running "Pineapple", after the jailbreak the phone will reboot). If Redsn0w is out, then just repeat step 7 .
  • If the Cydia label is displayed in white , then repeat step 5 , in step 6, tick only the " Just boot tethered right now " item, after the Jail completes, we get the working version of Cydia .
    Do not forget to go to Cydia and install all the updates:

  • Do not run Cydia while on your phone there is no connection to the Internet, EDGE or WiFi .
  • Check, or configure the Internet connection, and then run Cydia .
  • The reorganization of Cydia will begin. Wait, after the end of the reorganization, Cydia will close itself, and you will be thrown to the desktop.
  • Run Cydia again (to the question Who Are You? Answer Hacker (+ Command Line) ) and you will see important updates for Cydia , install them ( Complete Upgrade )

To speed up the operation of firmware 4.0.1 - 4.2.1 on the iPhone 3G and iPod Touch 2G, it is recommended:
  • disable wallpaper
  • disable multitasking
  • disable Spotlight search (settings - basic - home button - search Spotlight - uncheck all the checkboxes and reboot)
  • from time to time restart the phone by holding the Home and Power buttons for 10 seconds until the phone turns off

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

File manager with support for the updated iTunes iFunBox

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

For the possibility of having in future firmware an unattached Jailbreak (Jailbreak)
I recommend to save SHSH-certificates !!!

Frequently asked Questions:

If Redsn0w hangs on the message " Uploading ramdisk " / "exploiting with limera1n", and the message " downloading jailbreak data " is on the phone's screen and nothing happens more than 5 minutes

  • Run the Redsn0w file on behalf of the Administrator and the compatibility mode with XP SP2 / 3 .
  • Probably, the firmware file is not completely downloaded. Download firmware .ipsw again or from an alternative source.
  • Redsn0w on some configurations may hang because of the use of multi-core processors. Open " Task Manager ", in the " processes " find " Redsn0w.exe ", in the context menu select " Set compliance ... / SetAffinity ", leave a tick only for " CPU0 / CPU0 ".

Having an iPhone 4 and a Mac computer, can I save the SHSH certificate by flashing it to iOS 4.2b3, for the future use of an untethered jailbreak?

  • No! Subscription to SHSH-certificates below iOS 4.2.1 is already closed, more details here .
    Unattached jailbreak for iPhone 4, iPhone 3GS (New boot), iPod Touch 2G, iPod Touch 3G, iPod Touch 4G, iPad Greenpois0n

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

  • Follow the 9th paragraph of the instruction
  • Firmly reinstall the device, following the instructions in the instructions

During the iTunes firmware update error xxxx appeared

  • What error code means can be found in the corresponding forum thread
  • Either the Apple website

After Jailbreak and reboot your device on the screen, a white apple is burning.

  • Most likely, your device does not support untethered Jailbreak.
    With each shutdown (or full discharge), the device will have to connect it to a computer with Redsn0w installed and go through the entire hacking procedure (leaving only the " Just boot tethered right now " option)
    Unattached jailbreak for iPhone 4, iPhone 3GS (New boot), iPod Touch 2G, iPod Touch 3G, iPod Touch 4G, iPad Greenpois0n

How do I find out the version of BootRoom of my iPhone 3GS?

  • By serial number of the device ( Settings -> General -> About the device )
    Example: 87022Z635NQ
    We are interested in the 3rd 4th and 5th digits:
    xx 022 xxxxxx
    The third digit is the year (" 9 " -2009, " 0 " -2010)
    4,5- th figures a 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 borderline week (40-41), it's better to use the program described below.
  • Using the program iDetector

    • download iDetector
    • if Java is not installed, then go to, download and install the latest version
    • translate the phone into DFU mode (7th instruction point)
    • run iDetector, click on the button, learn the version of bootrom
    • To exit the DFU, press the Home + power button again.

Can I downgrade my modem 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 iPad modem (06.15.00)?

  • The modem version 06.15.00 has a version above any of the modems of all the currently released firmware 3G and 3GS phones, and therefore the update of phones with factory firmware via iTunes of your phone will result in error number 1015 , and the phone will remain in " recovery " mode ) from which to pull it out will not be so easy.
    And so you already have a modem 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 PwnageTool to jailbreak, then use this utility to create a custom firmware version 4.1 or 4.2.1 , when the program asks you about the installation of the BB (modem) 06.15.00, you should give it up . Complete the creation of custom firmware and use iTunes to flash the phone.
    • B ) If you use RedSn0w , then you have two options:
      • B-1 ) if you already have iOS 4.1 firmware, then flashing it again on iOS 4.1 , and when the window with error # 1015 appears on the screen, launch Tiny Unbrella and get the phone out of recovery mode. After that, run Redsn0w , follow its instructions, and when you get to the set of checkmarks, DO NOT NOTE the installation of the modem 06.15.00 , tk. you already have it.
      • B-2 ) if you already have iOS 4.2.1 , then you need to flash on iOS 4.1 (because iOS 4.2.1 does not allow you to get the phone out of the " recovery " mode, because it already has a stupid check on it correspondence modem / OS, 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 point 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 methods at the moment.