Tutorial: Prevent iPhone 4 Baseband Update iOS 4.2.1 Upgrade

So you have an iPhone 4 with a baseband that is unlockable by UltraSn0w and you want to upgrade to iOS 4.2.1?  You can easily do this with the latest version of Tiny Umbrella and GreenPois0n.

1.  Download the latest TinyUmbrella and GreenPois0n (GreenPois0n Mirror).

2.  Start Tiny Umbrella with your iPhone 4 plugged in.  Save your SHSH files for iOS 4.2.1.  (You should be saving your SHSH files whenever a new firmware comes out!) UPDATE: Apple has stopped signing SHSH blobs for 4.2.1, so if you do not have them saved, you can’t update to 4.2.1.  I will release a tutorial on how to update to 4.3 soon.

3.  Click on Start TSS Server.  If you get any errors, visit the TinyUmbrella FAQ page and fix the errors before continuing.

4. Launch iTunes and click on restore while holding down the shift key if you are on windows or the option key if you are on Mac.

5.  Select the iPhone 4 iOS 4.2.1 firmware file. If you dont have it you can download it here: iPhone3,1_4.2.1_8C148_Restore.ipsw (If it saves as a .zip file make sure to rename it to .ipsw).

6.  Once it is done restoring you should get a 1013 error.  Click on OK and close out of iTunes.  Your iPhone 4 will have the connect to iTunes logo displaying. If you get an error other than 1013, it means your baseband was updated. This is likely because you did not have the TSS server running or you are using a device other than an iPhone 4.

7.  We need to get the iPhone 4 into DFU mode by holding the home and power button until the screen goes black. Then count to 2 and let go of the power button but keep holding down the home button. Your screen will turn black if you did it correctly.  If not you will see an Apple logo and the screen will go back to the connect to iTunes logo.  If you see this you need to start step 7 over.

8.  Once you are in DFU mode start GreenPoison and follow Tutorial: Untether iOS 4.2.1 Jailbreak to jailbreak your iPhone 4 while preserving your baseband.

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  1. Luis says

    Thanks I did this when I jailbreaked my iPhone on iOS 4.1 and it preserved my baseband 1.59.00 so I hope it works once again since I want to update and jailbreak on iOS 4.2.1

  2. Kirk Dunn says

    Will this same process work for a 3Gs? I have two, one completely jb/unlocked at 4.1 and another with a fresh store install of 4.2.

    • says

      This tutorial will only work for the iPhone 4. The 3GS requires you to install the iPad baseband if you need ultrasn0w to unlock. I will see if I can make a tutorial for that soon.

      • Kirk Dunn says

        Thanks~I’m at 4.1 right now and it works. . .sort of. I have reception issues where the signal will drop out and compared to other phones of the same model the reception isn’t good. I talked to a “Genius” at an Apple store and he suggested doing a fresh install and setting up as a new phone. I have Pwnage Tool 4.1.3 and cooked ipsw’s all the way up to 4.1 but I’m pretty cautious about it. I’m in Japan and will take the phone back to the US eventually so I can’t afford to screw it up 🙂

      • Anthony says

        Dear Lei,

        I watched your tutorial and I find it really excellent. I had only few questions with regards to upgrading to version 4.2.1

        I had a jailbroken iPhone 4 with 4.1(8B117) firmware with 02.10.04 baseband I used before the old greenpois0n to jailbreak it.
        I am now setting up to upgrade it from 4.1 (8B117) to 4.2.1, my questions are;

        1. Do I need to download first the 4.2.1 firmware?
        2. Is their any way to upgrade it from 4.1 (8B117) to 4.2.1 by using greenpois0n?
        3. Once I restore it, will my customize setting and downloaded apps wipe away?

        I downloaded the latest tinyumbrella software as well as the greenpois0n-osx_rc5_2 and have it run already, I observed that there are saved SHSH appear on tinyumbrella (e.g. iPhone4 4.2.1 (8C148), iPhone4 4.3b2 (8F5153d) and iPhone4 4.3b3 (8F5166b), which one should I select?

        I be grateful for your assistance and waiting for your instruction.

        Thank you,


        • says

          Anthony. There is currently no unlock for baseband you currently have.
          1. Yes.
          2. no greenpois0n is just a jailbreaking tool.
          3. yes, a restore wipes your iPhone to factory settings like when you got it. You can sync your apps back after the fact.

  3. Saurabh says

    Nice video tutorial.
    Some queries though:
    Can I hacktivate with Greenpois0n ?
    I read somewhere that I can use GP to jailbreak and at activation screen, I can use redsn0w to install cydia which also hactivates. Can you please confirm that.

    I dont have original ATT sim with mem which I am sure is case with many people. So I need to be sure before I proceed.


    • Timmy says

      If you can get an AT&T sim card from somewhere it’s the best so you get legit activation records. The sim does not need to have service. You can run redsn0w after green pois0n

  4. Saurabh says

    Will any sim card do the trick??

    I thought you needed to have the original sim that came with device??

    Isn’t that so,?? Or I can just get any AT&T sim??

  5. Joelfefa says

    I saw the video that was not necessary to use the chip carrier, is hacktivation?
    Because I do not have the chip original, so I have to avoid restoring the device!

  6. Saurabj says

    I used gp and redsnow.. To jailbreak and activate my iPhone.

    But now my push is not working. Any solution to it ? Anyone else facing this?

  7. yen says

    my iphone 4 is already on 4.2.1 and is baseband 1.59, but it is now in recovery mode. I open tiny umbrella tried to kick out of recovery mode, but can’t.
    What do else do I need to do

  8. Guy says

    i followed the videotutorial and now i have 4.2.1 with BB 04.09.00
    i can’t use another sim provider!what did i wrong i’ve became BB 04.09.00?

    • says

      You didn’t follow it correctly. You probably did not pay attention to the TSS server part. You mist have TSS server running without any errors. Now you are going to have to wait for iOS 4.3 to be released before you can unlock.

  9. tommy says

    i followed the tutorial and i got stuck in middle !it keeping saying” preparing iphone to be restore”and stuck in the recovery mode??there is no error pop out and itune just keeping running forever??

  10. Raja says

    Does this work with the newest versison of itunes? i read somewhere that it does not, just trying to confirm? and will it work on windows? Thanks.

  11. ReyG says

    Hey Mike, I am a tmobile user and have been searching for an unlock tutorial that would answer some questions and yours seems to be what I am looking for. i purchased my iphone 4 in october 2010 and it came with ios 4.1 BB 02.10.04. I just heard today that Greenpoison came out and with JB the 4.2.1 ios. My basic question is if you think your tutorial will help me unlock my iphone 4 with its current setup? And if not what would you suggest I need to do?

    • says

      You can’t unlock that baseband yet. The dev team will not release the new unlock until iOS 4.3 is released. Stay tuned here. We will let you know as soon as it is available.

      • reyg says

        Ok thank you for clearing this up for me. I’m on the virge of canceling my tmobile and switching to AT&T, but I love the fact of having unlimited data with tmobile and I keep reading about the unlock coming when a new iOS is released.

  12. Westy says

    Hi, My itunes gets stuck on the Apple is verify update then i get an error saying itunes cant restore is this anything to do with tiny umbrella

    thank you

  13. MAI says

    Before you continue, you must have Saurik’s server in yoru host file. At the end of the file add the string gs.apple.com which is useful to redirect requests for certificates for authenticity that iTunes will make to the Saurik server. If you don’t know how to do that, follow the steps below:

    Mac users

    * Navigate to Go -> Go to Folder and enter the path /etc
    * Open the file hosts with TextEdit, add the following string gs.apple.comand save the file to your desktop.
    * Now return to the previous folder by following the same method and copy the text within this file by replacing the original file (If prompted for a password enter it and click OK)

  14. LatterDayAint says

    Hey… I see you get a lot of negative comments from people who obviously can’t follow a really simple step-by-step procedure, so I want to break the trend.

    Dude, you’re my hero. Seriously. I just followed your instructions like on your YouTube video I found online… in what seemed like mere moments, I was running 4.2.1 with a 1.59.00 baseband. I still have GPS functionality unlike those who’ve unlocked with an iPad baseband… and overall, I couldn’t be happier. Dude, you rock. Excuse my tone, but f*** all these people who can’t read and follow directions. Jeez.

    Keep up the good work. If I were able, I’d see that you were nominated for sainthood. THANKS!!!

  15. Michael says

    After jailbreaking with GP and I start iTunes I get: SIM card inserted in this iPhone does not seem to be supported. I can go no further. It is a T-mobile SIM. Do I have to use a At&T SIM to make this work? Or am i missing something?

    Thank you so much for all you do.

  16. Westy says

    Hey I can only get to the restore but and iTunes gets stuck on verifying software then get error saying servers are! Any ideas ??

  17. says

    weird when i start TSS server everything is cool but than i open up itunes and itunes gets stuck. when i pull out my iphone itunes react. than i plug it back in:

    02/14/2011 17:11:54.961 Starting TSS service on port 80 02/14/2011 17:11:54.972 TSS Accepting connections… 02/14/2011 17:13:15.308 Device disconnected: r0p | GigaVolt 02/14/2011 17:13:19.814 Device connected: r0p | GigaVolt 02/14/2011 17:13:19.841 Loaded History…

    I wanted to know if everything was oke, so i stopped/started the tss server but when i clicked the start TSS, itunes automatically closes…

    i restarted itunes but the ”preparing itunes for restore” is taking very long and after that i get an error: ”the iphone cannot be restored, an unknow error has occured (0xE8000013)

    Allot of problems for me…

  18. Mizo says


    i Have iphone4 4.2.1 lock by vodafone (firmware 03.10.01 )
    i just follow your instructions but my firmware not been change and i can`t use any other sim, could you please advice to unlock vodafone sim?

  19. lin says

    Thx for the detailed tutorial. Hw, I have a question re restoring my old contacts. I followed your video tutorial religiously, including the part re set up the iphone as a new iphone (as oppose to restoring to an old backup) after successfully upgrading with old BB and jbkg with gp. Now, my problem is how do I restore my contacts/text/mail/setting, etc.? Greatly appreciate your help ASAP!

  20. Alex Alaniz says

    ok so i never leave a comment bu this time i say amazing job man this video was sooo but sooo helpful i appreciate it 😀

  21. Shawn says


    I unlocked and jailbroke my iPhone 4 (baseband 1.59.0) to 4.2.1 using snowbreeze. (I preserved the baseband)

    I’m having issues with push notifications and youtube.

    I looked at SAM and Redsn0w and had issues since the deactivate settings are not showing up. (I’m using IPSW’s from felixbruns)

    I also went out and bought a Fido sim card because I was under the impression that my iPhone was a Fido phone. I’m with Rogers and iTunes still says that the sim card is invalid.

    What should I do to activate/deactivate my phone so that I can receive push notifications and get the right certificates.

  22. MAI says


  23. Noneed says

    Hi first of all I would like to say Great Tutorial it worked great when I tried it I am now on iOS 4.2.1 with 01.59.00 baseband working great…but when I was on the activation part I didn’t have an AT&T sim so I ran redsnow and installed cydia..then I installed ultrasnow through cydia and everything works fine…but I cannot activate facetime..it just says waiting for activation and nothing happens how can I fix this?

  24. naqsh says

    hi lei i hav iphone 4 4.2.1 baseband 3.10.01 can i unlock my iphone.and i recently move from portugal in uk my iphone is from portugal as well wat to do pls help me thnk you

  25. Jack says

    Hello,Is this jailbreak only available for iphone4 which firmware is 01.59.00? Since my iphone was already 03.10.01 when I bought it. Can I still go on with this step to jailbreak my phone? Thank you for answering 🙂

  26. enan says

    i have a iphone 4 4.0.2 jailbroken unlocked ultra snow… i have reseted network settings and it restarts stucked at recovery mode… can’t kick out of recovery with tiny umbrella… this tutorial works for me?

  27. says

    i have an iPhone wit ios 4.2.1 i try to upgrade ios to 4.3 but i got error 16xxx at dat time i was usin tiny umbrella. i try again by usin snow breeze but i got error 1013. when i connected it to itunes it show the phone is in recovery mode. any help. secondly i have saved the baseband file usin tiny umbrella into my flash drive, i was try to install it from different computer but is not workin any help to restore it to 4.2.1 and baseband 03.10.01. i need help

  28. Sarab says

    Hi I’m Sarab from India. I have Iphone 4 with 4.1(8B117) BB 01.59.00.(Allready Jailbroken) I want to upgrade my iPhone with 4.2.1 without locking my device. Will it safe method to upgrade my phone with your instructions? Please reply …

  29. Arshan says

    PLEASE HELP ME…..!!i hav done all the steps showed by u…but after the greenpois0n jailbreak ….m still getting the SLIDE FOR EMERGENCY screen….and my itunes is showing me THE SIMCARD IN THIS PHONE APPEAR TO BE NOT SUPPORTED….plz help me if anyone hav a solution…

  30. Tony says

    Wonderful stuff, thanks for the detailed instructions. I feel bad for the guy who didn’t have TinyUmbrealla server running LOL

  31. Jeremy says

    I am a bit confused about what you mean by the part below, can you clarify? I am currently using an iPhone 4 unlocked on 4.0 and BB 01.59. I am about to attempt to follow this tutorial and get to 4.2.1. Here is what throws me off:

    “Start Tiny Umbrella with your iPhone 4 plugged in. Save your SHSH files for iOS 4.2.1. (You should be saving your SHSH files whenever a new firmware comes out!) UPDATE: Apple has stopped signing SHSH blobs for 4.2.1, so if you do not have them saved, you can’t update to 4.2.1. I will release a tutorial on how to update to 4.3 soon.”

    Mainly the part where you say “save your SHSH files for 4.2.1”. Are you basically saying to just make sure and save the CURRENT FW SHSH blobs? Or am I somehow saving an SHSH on 4.2.1 before even starting?

    Thanks for clarification!

  32. says

    I have done everything just i havent install redsn0w but i have install ultrasn0w and my phone everything was okey soon as some one try to give me a call it goes to voicemail and is not possible to contact how can i fix this or what is it any ideas?

  33. Samir says

    hi all . hey all my friends please help me . how to unlock my iphone 4 ios 4.2.1 ( bb 03.10.01 ) how to unlock my iphone ????????? ultrasn0w can unlock my iphone 4 ? i`m wait you . please help me

  34. mark says

    I completed jailbreak using jailbreakme.com

    Now, I only get a screen with the apple logo. When I attempt to reset I just get the apple logo screen, occasionally I get the screen which tells me to plug in usb and open iTunes.

    I previously had bb 01.59 and iSO 4.0 before running jailbreak.

    When I plug in the iPhone 4 and open iTunes I get a message stating that iTunes detected a iPhone in recovery mode and must update.

    If I update will I be able to get back to my original bb and iOS? I believe it said my iPhone software is up to date, so does this mean I no longer have 01.59?

    I need to jailbreak/unlock this phone.


  35. raaz says

    i have iphone4 ios 4.0 baseband 1.59.00 and wants to restore by 4.2.1 .i tried many more time but everytime i got some error of 3194. can anyone help me????how to restore ,jailbreak and unlock my iphone?????

  36. Daniel says

    My friend i have a iphone 4 baseband 01.59.00 and firware 4.0.2 and when i try to restore on itunes folup your tutorial i don´t get the error 1013 i get the error 1604 and now my iphone is stuck on conect to itunes please help me how can i fix thanks a lot…

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