• 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. vruls's Avatar
      vruls -
      Hey wtf whreis the one for ipt 3rd gen i really need to downgrade mine
    1. MexiChriS's Avatar
      MexiChriS -
      Okay wow, ******* great, this **** gets posted once I take forever to do this last night/morning ahaha did learn a lot though from it!

      Only question is; since I downgraded before this post, my iPhone 3GS is: jailbreak: redsn0w firmware: 3.1.2 baseband: 05.13.04 (from downgrading iOS 4) that really can't even use Cydia (crashes on start). How do I go about properly jailbreak this time around + upgrade back to iOS 4!?

      As I know I can but in 'theory' it seems off as it states in latest Pwnage that you can't jailbreak with new baseband from iOS 4. Although I am jailbroken from redsn0w on 3.1.2 ...kinda have a hybrid iPhone or something haha lost HELP!
    1. mardinn's Avatar
      mardinn -
      Thank you for this guide. People are taking a piss. Making 4 fkin jailbreaks for iDevices 2G 3G.. but no 3gs.. eh.. Well lets see what happens ;p
    1. kenyan's Avatar
      kenyan -
      Guys quick question, is it possible to Downgrade to 3.1.2 if you have SHSH of 3.1.3 saved on Cydia?

      I would like to downgrade to 3.1.2, coz I have the phone JB with Spirit. If I can, then will JB with Blackra1n, then upgrade to IOS4. Any pointers guys.
    1. Antman217's Avatar
      Antman217 -
      Since mac doesn't have iReb you should download Recboot which is available for both windows and mac and it simply has two buttons, enter recovery mode and exit recovery mode. Obviously just click exit recovery mode and you will reboot and be back on 3.1.x. This is what I used to downgrade my 3G on my MacBook.
    1. Logan80's Avatar
      Logan80 -
      Stuck in the recovery loop and I've had no success with iReb or iRecovery. I've installed the libusb, nothing. Tried Blackra1n, no bueno. I'm running Win7 64 bit if this helps.
    1. index's Avatar
      index -
      Quote Originally Posted by Logan80 View Post
      Stuck in the recovery loop and I've had no success with iReb or iRecovery. I've installed the libusb, nothing. Tried Blackra1n, no bueno. I'm running Win7 64 bit if this helps.
      This was my exact problem. iReb/iRecovery do not work. Period.
    1. olivo42's Avatar
      olivo42 -
      I'm still stuck in the emergency calls screen with iOS4 and can't get to 3.1.2

      i've tried everything posted here and got NOTHING

      HELP PLEASE...

      I have win7
    1. Azulfuego's Avatar
      Azulfuego -
      After doing this and failing at JB I went back to 4.0. 3G no longer works. I have tried everything I know to get it going, be careful.
    1. olivo42's Avatar
      olivo42 -
      i think this is the part i'm doing wrong: Fix Recovery Boot Loop

      Tell me the correct way to do this...perhaps i'm doing wrong
    1. finalfantasy's Avatar
      finalfantasy -
      ok im lost

      i put the in the host file the saurik adress and deleted all others in the host except local and sauriks adress, in cydia mine says its green and has in file 3.0 3.12 3.13. i shut off my phone. put it in DFU mode, told it to shift restore to 3.1.2 that i downloaded from here. when it gets to VERRIFYING WITH APPLE it gives me the error the Iphone could not be restored. an unknown error occrured (3194)

      what am i missing?
    1. kyle01's Avatar
      kyle01 -
      Quote Originally Posted by dq13 View Post
      try copying the file to the desktop, modify it and then copy and replace back to the /etc folder
      Easy fix. Copy it to your desktop like mentioned, edit. Delete original/replace with desktop version. I had to input my mac pw to do this, just click "Authenticate" when it prompts, and input your system pw. Should work.
    1. philo's Avatar
      philo -
      You can downgrade from 4.0 to 3.x if you have the shsh blobs even if you have a new bootrom. I'm sitting here with my 3GS that I just did this on last night for kicks.
    1. finalfantasy's Avatar
      finalfantasy -
      i know it can be done but i want to know those who had same problem then me how they fixed it.

      i put the in the host file the saurik adress and deleted all others in the host except local and sauriks adress, in cydia mine says its green and has in file 3.0 3.12 3.13. i shut off my phone. put it in DFU mode, told it to shift restore to 3.1.2 that i downloaded from here. when it gets to VERRIFYING WITH APPLE it gives me the error the Iphone could not be restored. an unknown error occrured (3194)
    1. RGee's Avatar
      RGee -
      nice thread thanks u
    1. olivo42's Avatar
      olivo42 -
      Quote Originally Posted by finalfantasy View Post
      i know it can be done but i want to know those who had same problem then me how they fixed it.

      i put the in the host file the saurik adress and deleted all others in the host except local and sauriks adress, in cydia mine says its green and has in file 3.0 3.12 3.13. i shut off my phone. put it in DFU mode, told it to shift restore to 3.1.2 that i downloaded from here. when it gets to VERRIFYING WITH APPLE it gives me the error the Iphone could not be restored. an unknown error occrured (3194)
      I'm having the same problem..

      I'm still stuck at the emergency calls screen with FW 4.0

      What are we missing?
    1. kyle01's Avatar
      kyle01 -
      This was so painfully simple. The only problem I ran into was not being able to edit the hosts, which you simply copy it to your desktop, edit, then replace the original with the edited version.

      Also had a "carrier update" prompt after updating.

      BTW. When choosing your firmware through iTunes Restore, it's easier if you have a custom firmware rather than the original available. Avoids any DFU/Recovery Mode issues...

      Good luck!!
    1. finalfantasy's Avatar
      finalfantasy -
      FOR 3194 ERROR PPL I HAVE FOUND THE SOLUTION

      Go into HOST file, check to see if your localhost ip is same then mine if not rmeember the number and replace the one im posting with yours. DELETE EVERYTHING and paste THIS




      # Copyright (c) 1993-2009 Microsoft Corp.
      #
      # This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
      #
      # This file contains the mappings of IP addresses to host names. Each
      # entry should be kept on an individual line. The IP address should
      # be placed in the first column followed by the corresponding host name.
      # The IP address and the host name should be separated by at least one
      # space.
      #
      # Additionally, comments (such as these) may be inserted on individual
      # lines or following the machine name denoted by a '#' symbol.
      #
      # For example:
      #
      # 102.54.94.97 rhino.acme.com # source server
      # 38.25.63.10 x.acme.com # x client host

      # localhost name resolution is handled within DNS itself.
      # 127.0.0.1 localhost
      74.208.10.249 gs.apple.com
      # ::1 localhost

      what i was doing wrong was basicly adding # before the 74.208ect.... and that i guess screws everything lol
    1. loocfa's Avatar
      loocfa -
      first of all im not a noob, as you can see ive been on this forum since day one, and jailbroken all firmwares from 1.0 to 3.1.3 but this has really got the best of me and im trying everything i can to get to 4.0 jb.


      i have 3gs on 3.1.3 sprint jailbroken, modem on 5.12.01, model MC, week number 32,

      and i have both 3.1.2 and 3.1.3 shsh files save to cydia, as well as the same firmware bundles i used.

      i know the new bootrom is unjailbreakable , but i have an old build week (32), does this make a difference?

      by downgrading to 3.1.2 and jailbreaking will it change my bootrom or help me in anyways get to jb 4.0?

      has anybody had any success downgrading to 3.1.2, and upgrading to 4.0 and jailbreaking on 3GS?


      unfortunately i am currently on 3.1.3, as i bought this 3gs off criaglist and was already updated,

      if you have any info that might help that would be awesome,
      i know my way around both pcs and macs, but preferably mac,


      thanks for reading
    1. olivo42's Avatar
      olivo42 -
      how can i get a custom FW 3.1.2?