• Your favorite

    Apple

    ,

    iPhone

    ,

    iPad

    ,

    iOS

    ,
    Jailbreak
    , and
    Cydia
    site.
  • [Guide] How To Downgrade iOS 4 : iPhone 3GS


    In the flurry of upgrades and jailbreak tools, many may have come to the realization that they are not yet ready for iOS 4 for various reasons, wether it be a new bootrom, or you simply miss your Jailbroken apps from Cydia, this guide will help you downgrade your recent update to iOS 4 back to 3.1.x. While it is highly recommended to restore to 3.1.2, some of you may not have that option, but only use 3.1.3 as a last resort. However, it is important to note that if you are downgrading, in order to upgrade to iOS 4 JB, you MUST be on 3.1.2. The only jailbreak for 3.1.3 is Spirit, which is NOT compatible for upgrading to iOS 4 Jailbroken.

    Before we even get started, you must have your SHSH blobs on file with Saurik's server. You can tell if you have this by opening cydia and seeing a message similar to this:



    If you are 100% sure you have this message, and recall choosing the "Make My Life Easier" option when you first launched Cydia, then it's time to proceed. If you unfortunately do not have these saved, and are already on iOS 4, then there is nothing you can do.

    Ok, so you made it past the hump. You have SHSH blobs on file via Saurik's Cydia server, which means your going to be able to downgrade just fine. The next question is, which firmware would you like to downgrade to. In my case, I don't have SHSH blobs on file for 3.1.2, so I will be downgrading to 3.1.3 instead.

    Grab your stock firmware from the links provided at the end of this thread. Make sure you are using the one you have SHSH blobs on file for.

    Now that we've got this far, its time to begin:

    Note: This guide ONLY applies to the 3GS

    Step 1: Modify the Hosts file

    In order to trick iTunes into connecting to Saurik's server instead of Apple, we need to modify the hosts files. This applies to both Windows and Mac users. By doing this, we are able to get iTunes to think that our device is eligible for a downgrade. Normally when a new firmware is released, the older firmwares are no longer signed by Apple, thus preventing downgrading, but by connecting to Saurik's server, we bypass this issue.
    1a: Modifying Windows Hosts file



    Browse to Windows\System32\drivers\etc\. Inside this directory you should be able to find a file named "Hosts". Open this in Notepad and add the following line to the bottom.

    74.208.10.249 gs.apple.com
    Due to some restrictions on Windows you may have to create a copy of this file on your desktop and then drag and drop it to replace.



    1b: Modifying Mac Hosts File

    The same idea as windows here, only in a different location. On your Mac, Open Finder, and choose Go from the toolbar, and then Go To Folder. Type in the following: etc/ .



    This folder should pop up, and inside you'll see the hosts file. Open this file with textedit and add the following line to the bottom.

    74.208.10.249 gs.apple.com
    Save the file.



    2: Install Firmware Manually



    Now you can launch iTunes, shift click, or ctrl click, Restore, choose your firmware, and the downgrade begins. Some of you may not have any problems from here, but some of you will end up in recovery mode by the end of it. Do not worry, this is normal. Now we just need to force the phone out of recovery mode.




    3: Fix Recovery Boot Loop

    In our case, I used iReb to easily fix the recovery boot method. This is of course on Windows, but you can also use many of the methods out there to fix the recovery loop. If you need further help with this, post a reply.

    4: Welcome Back to 3.1.x.

    Your back. Now you can patiently wait for further development on iOS 4 in the meantime and have all your fun apps back. Hope this helps everyone. I Will add photos shortly.



    Resources & Links:

    We have had guides for downgrading the 3GS to 3.1.2 for awhile now check em out if you need more instruction
    Downgrade 3GS to 3.1.2 on a Mac
    Downgrade 3GS to 3.1.2 on Windows


    3.1.2 Firmware (Official Apple Links)
    Download iPhone OS 3.1.2 for iPhone 2G
    Download iPhone OS 3.1.2 for iPhone 3G
    Download iPhone OS 3.1.2 for iPhone 3GS

    3.1.3 Firmware (Official Apple Links) - Only use these if you do not have 3.1.2 on file.
    Download iPhone 3.1.3 firmware for iPhone 2G
    Download iPhone 3.1.3 firmware for iPhone 3G
    Download iPhone 3.1.3 firmware for iPhone 3GS

    Utilities
    iReb for Windows (Mac Soon)
    iRecovery (Mac & windows)
    This article was originally published in forum thread: [Guide] How To Downgrade iOS 4 started by nickhesson View original post
    Comments 174 Comments
    1. MrBucket101's Avatar
      MrBucket101 -
      firmware umbrella automates all of the host modifications through its built in TSS server.

      might use it instead for simplicity
    1. dq13's Avatar
      dq13 -
      Quote Originally Posted by index View Post
      I'm stuck in a recovery loop and iReb does absolutely nothing. I click the 3GS button and absolutely nothig happens. It's a 3GS old bootROM.
      if iReb doesnt work, try iRecovery (download link on the first post as well)
    1. index's Avatar
      index -
      Quote Originally Posted by dq13 View Post
      if iReb doesnt work, try iRecovery (download link on the first post as well)
      That doesn't work either. When I try to run iRecovery -s, it tells me no iPod/Iphone found.
    1. olivo42's Avatar
      olivo42 -
      I donnot know what the heck i'm doing wrong..
      I'm stuck in the emergency calls screen with iOS4.
    1. tbdsonicx2's Avatar
      tbdsonicx2 -
      Yea i found out about this yesterday now my iPhone is re-jailbroken and in tip top shape :-)
    1. index's Avatar
      index -
      Quote Originally Posted by index View Post
      That doesn't work either. When I try to run iRecovery -s, it tells me no iPod/Iphone found.
      Anyone? Why aren't these tools working? Is there any other way to fix a recovery mode loop?
    1. olivo42's Avatar
      olivo42 -
      Hapens the same to me... i cannot run "saten auto-boot true" nor the rest... please tell me how to
    1. dazzer1983's Avatar
      dazzer1983 -
      Quote Originally Posted by iLaw-One View Post
      Can someone please post a guide to jailbreaking the iphone 4 (once the tool is released)?? I need to jailbreak this beautiful bird as soon as o2 have activated my sim!
      I'm stuck using wifi for the moment...not complaining, but just want a complete phone
      You cant yet
    1. olivo42's Avatar
      olivo42 -
      Not yet...

      Please help us out with an xplicit tutorial... i'm new in this..

      i have windows7 and still stuck in the emergency calls screen with FW 4
    1. matistight@yahoo.com's Avatar
      LISTEN! WHEN YOU RUN IRECOVERY, HIT (WINDOWS BUTTON)+R AND THEN BROWSE, FIND THE I RECOVERY FILE, AND ADD " -s" TO IT!!!!!!! HOPEFULLY THIS HELPS!!!!!
      ummm im pretty sure its not "saten auto-boot true" hahhaah definatly not saten haha

      and mms still not working
    1. dq13's Avatar
      dq13 -
      Quote Originally Posted by olivo42 View Post
      Not yet...

      Please help us out with an xplicit tutorial... i'm new in this..

      i have windows7 and still stuck in the emergency calls screen with FW 4
      this tutorial can not be any more explicit... did you check back the instructions? the added pictures... If you are stuck on emergency calls is because the phone has not been activated, instert a valid ATT SIM card to get pass the emergency calls screen
    1. Punisherrrrrr's Avatar
      Punisherrrrrr -
      So this wouldn't work for the iPod Touch 3g?
    1. olivo42's Avatar
      olivo42 -
      Thnaks
      but the only iRecovery file I Found was the iRecovery.exe
    1. pimpinpapoii's Avatar
      pimpinpapoii -
      Quote Originally Posted by dq13 View Post
      this tutorial can not be any more explicit... did you check back the instructions? the added pictures... If you are stuck on emergency calls is because the phone has not been activated, instert a valid ATT SIM card to get pass the emergency calls screen
      can you add some pictures for iRecovery and iReb?

      there are no detailed instructions for this section.


      Thanks!
    1. aminsamizadeh's Avatar
      aminsamizadeh -
      I saved my SHSH when i was on 3.1.2 but now i can only downgrade to 3.1.3....i don't know why!!!!
    1. reggie6801's Avatar
      reggie6801 -
      I'm trying to point iTunes to the 3.1.2 firmware but the folder that I downloaded from modmyi doesn't have a IPSW? Am I missing something?
    1. olivo42's Avatar
      olivo42 -
      ok, I went into the -s ..ajaj... but now i have a error 3014 on itunes and doen't restore to 3.1.2

      I'm still stuck in the emergency calls screen with FW 4

      Tell me what'm i missing?
    1. dq13's Avatar
      dq13 -
      Quote Originally Posted by reggie6801 View Post
      I'm trying to point iTunes to the 3.1.2 firmware but the folder that I downloaded from modmyi doesn't have a IPSW? Am I missing something?
      did you download the firmware with internet explorer? if so, then IE changes the extension to .zip, so you have to rename the file and change it back to .ipsw, that's why iTunes doesn't find it
    1. olivo42's Avatar
      olivo42 -
      i have a error 3014 on itunes and doen't restore to 3.1.2

      I'm still stuck in the emergency calls screen with FW 4

      please Tell me what i'm doing wrong?