Now that Greenpois0n RC5 finally provides the long awaited iOS 4.2.1 untethered jailbreak (without the need of SHSH Blobs), many iPhone 4 owners with unlocked iPhones’ have been told to hold off upgrading to 4.2.1 as you will lose the ability to unlock (for now).

But thanks to TinyUmbrella developer @notcom, there is now a way to upgrade to iOS 4.2.1 without upgrading your baseband. Unfortunately, currently you will only be able to unlock your iPhone 4 on the older 1.59.00 baseband (modem firmware). So if you are not on the older baseband, you will not be able to unlock your iPhone 4.

For those of you with the older 1.59.00 baseband, follow the guide below to preserve your iPhone 4 baseband and unlock and jailbreak your iPhone 4 on iOS 4.2.1…

Note: If you are unsure as to what baseband your iPhone 4 is on, launch Settings > General > About  > Modem Firmware.

Step 1: Download TinyUmbrella from here

Step 2: Connect your iPhone 4 & Launch TinyUmbrella

Step 3: Click On the “Save SHSH” button

Step 4: Now, Click on start the “TSS Server” button

Step 5: While the TSS server is running, Launch iTunes

Step 6: Now, Click on Restore in iTunes (Don’t Click on Update)

Step 7: During the Restore Process, iTunes will give you Error 1013. Don’t panic, this is good. This error means your baseband has been preserved. Exit out of iTunes.

Step 8: Next, jailbreak your iPhone 4 with Greenpois0n RC5 (follow our tutorial here). This will jailbreak your iPhone 4 as well as kick it out of Recovery Mode.

Step 9: Because Greenpois0n does not support hacktivation, you will need to find an official SIM card (doesn’t need to be activated), insert it in the iPhone 4 and connect to iTunes. This will bring you to the homescreen. Once you are on the homescreen, you will no longer need the official SIM card.

Step 10: Follow our tutorial here to unlock your iPhone 4 on baseband 1.59.00.

All done! Enjoy your unlocked and jailbroken iPhone 4 on iOS 4.2.1!

  • An official SIM? We can’t use a Tmobile SIM?

    • Kickstar13

      No. Greenpois0n does not support hactivation. So to get off the Emergency Dialer screen you will need to insert an AT&T SIM card (doesn’t need to be activated) and then connect to iTunes so that you can get to the homescreen.

  • EgoHot

    I preserved BB 01.59.00 when I first got my replacement iPhone 4 (it originally had 4.0.2 installed) but I do NOT have SHSH blobs for 4.0.x. Is it still safe to try this method? or should I wait for PwnageTool to be updated? I don’t rely on unlock but I’d really like to preserve that baseband for future resell value.

    • Kickstar13

      It’s safe. I tested it on my Unlocked iPhone 4 as well.

  • aLb3Rt

    I’m on 4.1 BB 01.59.00 and would like to update to 4.2.1 In step6 in your guide you said to restore, is it safe to use the 4.2.1 FW from this sites download page do does it have to be from apple?! what do you suggest?! Tnx!

    • Kickstar13

      Yes, it’s safe. But make sure you follow directions carefully. When TinyUmbrella TSS server is running, it will preserve Baseband and give you error 1013. Then proceed to jailbreak with greenpois0n RC5.

  • alan

    How long be wait my phone to unlock 4.2.1 bb03.10.01 ? If i jailbreak the iphone is ok and unlock later,right? please help…….

  • Dubai_lad

    Official SIM? further explanation please.

    • Greg

      AT&T for iPhone from US.

  • phil

    is this just for the mac?

  • garry

    windows version is out!!! however i cant download it somehow. im on iphone :p

  • EgoHot

    I was unable to exit out of recovery after getting the 1013 error 🙁

    so I’m going back to 4.1 for the time being

    • Kickstar13

      You didn’t need to get out of recovery. Greenpois0n will automatically kick your iPhone out of recovery as well as jailbreak it.

  • EgoHot

    I gave it another try and it worked!!!!

  • Thanks for the info for iPhone 4’s but is this possible with the 3Gs (with existing baseband)



    • Kickstar13

      No, this method works for iPhone 4 ONLY.

  • Monkers

    Bah, still no bloody good. No further forward. Baseband 2.10.00 and Win 7. Come on people, sort it out please. There is no way Apple are going to redo 4.3 to shut JB down. Publish please George.

  • Monkers

    Dyslexic fingers, baseband 02.10.04

  • None

    When is the unlock coming??

    • Kickstar13

      Once iOS 4.3 is officially released to the public.

  • Night

    I know it might not be possible to know, but will this method work with the Windows version of Greenpois0n, and will this method work to preserve the base band for future iOS?

    • Kickstar13

      Yes, once the WIndows version of Greenpois0n is released it will preserve the baseband. Just follow same directions above. This is ONLY TESTED with iOS 4.2.1.

  • EgoHot

    Ok. So I can get greenpois0n to kick it out of recovery but once I try to restore from backup, it freezes iTunes and I have to Force Quit it. I’ve sadly gone back to 4.1

    • iKing

      Hey I was having the same problem. Fortunate for me I have a Mac and Windows so i think the problem is Windows.

      • iKing

        simple solution update ur itunes to 10.1 and u should be good

  • Nitesh

    @kickstar13 hi bro,in the 9th step you said that we should need an official sim is that necessary i think we can use the redsn0w there isn’t that because it also hactivate our iphone,if not why?

    • Kickstar13

      Yeah, you can alternatively use redsn0w to hacktivate it as well if you don’t have an official ATT sim card.

  • Moshi30

    Hi. Im on fw 4.1 with baseband 01.59 unlocked and jailbroken. I plan to upgrade to 4.2.1 – if i do so do i lose all data on my phone? Do i click back up from the itunes? Thank u

    • Kickstar13

      To save all your data, just backup all your stuff in iTunes. And then after it’s done restoring, jailbreak with greenpois0n, and then connect to iTunes and it will give you the option to restore all your stuff back onto your iPhone.

  • mike
  • iMo.

    Is there a work around the AT&T official sim?

    I have an US iPhone 4 but I don’t live in there.. It’s impossible to get an AT&T sim card here…

    • Kickstar13

      You can alternatively use redsn0w to hacktivate the iPhone (just checkmark the “install Cydia” option.

      • Night

        @Kickstar13, thanks for all the information, but could you explain step by step this process, (adding to the steps you posted) as I’m afraid to mess this up.

        Or at lease, tell me this, after the TinyUmbrella businesses (that remains the same) I have to jailbreak using redsnow (to activate the phone) and then use greenpoison to untethered? or I can first use greenpoison and then I should use redsnow?

        Once again thanks a lot

      • Kickstar13


        After you preserve your baseband with TinyUmbrella, then jailbreak using Greenpois0n.

        Then to activate the iPhone 4, using redsn0w, select the “Install Cydia” option ONLY (DO NOT select the JailbreakMonte option).

        This will install cydia as well as hacktivate your iPhone 4.

        Let me know how it turns out!

      • Night


        It worked like a charm!!! I bow before your mighty knowledge

  • Mo

    some other sites did not include step 9 in their tutorials for this..

    is it really necessary?

    • Kickstar13

      You will need the AT&T SIM card to get to the homescreen, otherwise you will be stuck on the Emergency Dialer screen.

      Alternatively, you can use redsn0w 0.9.7 beta6 to hacktivate your iPhone. Just make sure to checkmark ONLY the “install Cydia” option.

      • Mo

        do I do this after or before I use TinyUmbrella?

      • Kickstar13


        After you are done restoring with TinyUmbrella (which will preserve your Baseband) then jailbreak using greenpois0n. Then insert your official sim card in there and plug your iPhone into iTunes. It will get you off the Emergency Dialer screen.

  • Help123

    Why does the prompt tell me that TSS server is not running? Below is the log:

    02/06/2011 18:03:14.223 CYDIA DOES NOT HAVE YOUR SHSH FOR iPhone4 4.2b3 (8C5115c) THERE IS NO WAY FOR YOU TO GET THEM. SORRY. YOU ARE JUST TOO LATE. 02/06/2011 18:03:15.441 You have saved your iPhone4 4.3b3 (8F5166b) SHSH locally and the request was sent to CYDIA. This means that CYDIA DOES have your SHSH. Do NOT bug semaphore about the Cydia home page showing this version. 02/06/2011 18:03:17.235 You have saved your iPhone4 4.3b2 (8F5153d) SHSH locally and the request was sent to CYDIA. This means that CYDIA DOES have your SHSH. Do NOT bug semaphore about the Cydia home page showing this version. 02/06/2011 18:06:55.095 This device isn’t eligible for the requested build. 02/06/2011 18:06:55.105 CYDIA DOES NOT HAVE YOUR SHSH FOR iPhone4 4.0.2 (8A400) THERE IS NO WAY FOR YOU TO GET THEM. SORRY. YOU ARE JUST TOO LATE. 02/06/2011 18:07:05.040 Server-side error. Cydia is likely overloaded… 02/06/2011 18:07:05.050 Your SHSH for iPhone4 4.0.1 (8A306) was NOT saved. 02/06/2011 18:07:19.447 You have saved your iPhone4 4.2.1 (8C148) SHSH locally and the request was sent to CYDIA. This means that CYDIA DOES have your SHSH. Do NOT bug semaphore about the Cydia home page showing this version.

    • iKing

      Did u press Start TSS server and not save shsh?

    • wrx7182

      I have the same problem WTF!!!!

      • wrx7182

        figured it out…..

  • Can someone confirm the redsn0w workaround to the official SIM requirement, does it work?

    • StillBlue

      Yes, worked a treat for me. I had previously JB mine with Redsn0w although the JB was tethered. I then ran Greenpoison over the top and now I have a perfect untethered JB with no need to activate as Redsn0w had applied the hacktivation patch.

      I personally also removed the animated logo as I didnt like it.

  • Uri

    Does this work on a iPhone 3GS?

    • Kickstar13

      As stated before, this preservation method only works for the iPhone 4.

  • prakash

    @stillBlue – how did you remove the animated logo

    • Kickstar13

      To remove the animated boot logo, SSH to usr/bin and then delete the “animate” file.

  • muscle99

    I get error code 404

    What can I do?

  • muscle99

    I’ve got iPhone 4 with 4.1.

  • Tony

    Hi, thx for the tutorial, it really works, but now another problem comes out.
    The battery drains a lot, and it gets warm. I think that ‘s dut to the phone is trying to find valid push certificate.
    I know that iphone3g/3gs can use redsnow 0.9.6b6 with SAM to fix the battery drain problem.
    But for the Iphone4, I can’t find deactivate option in redsnow 0.9.6b6 for iphone4 to work with SAM.
    Another thing to do is to turn off 3g, but you won’t get any push notify when you do that.
    Is there any other way to fix this?


  • warmywhite

    Hi, I have an iphone 4 Jailbroken using & unlocked using ultrasn0w. I have a cut down O2 sim (the iphone was locked to Vodafone in the UK).

    My Version is 4.0.1 (8A306)
    Modem Firmware 01.59.00
    Model MC603B
    OSX 10.6.6

    If I use this method will I lose the unlock & no longer be on the o2 network?

    • Kickstar13

      Follow the tutorial in the article and your iPhone 4 1.59.00 Baseband will be preserved and you will have an unlocked and jailbroken iPhone 4 which you can use on any GSM network worldwide.

      • muscle99

        Well as I said, when I hit the restore button it says do you want to backup, I say no and then it asks again, I press restore but it returns very quickly with the 404 error!
        (iPhone 4 with 1.59.00 Baseband and 4.1 FW).

      • muscle99

        I tried on both machines Win XP and Win 7.

      • muscle99

        And an Mac OS X 10.6.6, an all 3 machines with latest iTunes and TinyUmbrella 4.21.07!

  • vhora salman

    if i have unlocked i phone 3g with 4.0.1 and now i want to upgrade it to 4.0.2 than i want to unlock another time

  • Zeeshan

    fuck of F U .C K
    my phone is llocked
    Ma Ki Choot

  • Zeeshan

    when i do this on windows 7 my iphone 4 is locked

  • doll

    which version of redsnow do i need to download after following the above tutorial.please reply soon.and will this method work on windows 7.

    • Kickstar13

      You don’t need redsn0w unless you want to hactivate the iPhone and don’t have an AT&T sim card (doesn’t need to be activated).

  • moondoll

    dear kickstar i brought my iphone from uk and had to unlock it in india,using an at&t card(i gave it to a person who charged 500rs for doing it)nw i want to upgrade to 4.2 from 4.0 thats why i wanted to know wether i’ll need a redsnow to hactivate or is the above process enough by using my old vodafone sim card which i had to cut.thnk u.