June 12, 2024
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Posted November 29, 2010 at 11:56pm by iClarified
Portuguese (Brazil)
These are instructions on how to jailbreak and unlock your iPhone 3GS on the 4.2.1 firmware using RedSn0w for Mac. If you have an iPhone 3GS with the new bootrom you will only be able to perform a tethered jailbreak at this time. This means you will need Redsn0w's assistance to boot into your jailbroken device.

If you want to use Redsn0w to jailbreak a lower firmware version you can find the appropriate tutorial here.

During this process you can update your baseband to the 06.15 version. If you are on 05.14 or 05.15 or higher you will need to do this to unlock. You do not need to do this for jailbreak only. Please read the following very carefully before deciding whether to do this. You can find out baseband version here.

1. There is no way to come back down from 06.15, and there’s no hiding the baseband version from Apple. You’ll be voiding your warranty in a very obvious way.
2. If some future baseband comes out with a critical fix, you won’t be able to update to it if it remains down in the 05.xx sequence (then again, you wouldn’t update to it if you wanted to keep your unlock anyway).
3. Starting with FW 4.2.1 if you have 06.15 on your iPhone you won’t ever be able to restore to stock firmware (it will fail). You’ll need to only restore to custom IPSWs (then again, if you’re unlocker you should already be doing that).
4. There are reports that 06.15 may disable your GPS. The iPhone Dev-Team is currently working on a fix.

Don’t update to 06.15 if you don’t need to! Only do this if you need the unlock and you’re stuck on 05.14 or 05.15, and you’re willing to assume the above risks. If your baseband is already unlockable and you are on a lower firmware version then use this custom PwnageTool bundle to update to 4.2.1 without upgrading your baseband.

Step One
Create a folder on your desktop called Pwnage

Download RedSn0w from here and place it in the Pwnage folder. Likewise, download the latest 4.2.1 firmware from below and place it in the same folder.

4.2.1 (3GS): iPhone2,1_4.2.1_8C148a_Restore.ipsw

Extract the redsn0w app from the RedSn0w zip file by double clicking it.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Step Two
***If you are already on iOS 4.2.1 you can skip this step. If you are on an unlockable baseband and on a lower firmware you should use PwnageTool instead to update without upgrading your baseband.

Connect your iPhone to the computer and launch iTunes.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Select your iPhone from the list of devices on the left. Now hold down Option and click the Restore button. Restore is preferred as it won't create any wasted space on your iPhone.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Navigate to the Pwnage folder on your desktop and select the 4.2.1 firmware ipsw. Click the Choose button to continue.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Step Three
Once iTunes has finished updating your iPhone to the desired firmware open the Pwnage folder on your desktop and launch the redsn0w application from the redsn0w folder we extracted earlier.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Step Four
Once RedSn0w opens click the Browse button
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Step Five
Select the 4.2.1 firmware ipsw we placed in the Pwnage folder on our desktop then click Open.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

You will be asked if this device is a newer fixed model. If yours is then click the Yes button; otherwise, click the No button. At this time you can only perform a tethered jailbreak on the newer model.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Step Six
Once the firmware has been verified click the Next button to continue.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Step Seven
RedSn0w will now prepare the jailbreak data
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Step Eight
From this window you can select the jailbreak options you would like.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Verbose boot displays detailed information on boot of your device and is generally only needed by developers and advanced users.

Make sure Cydia is selected. For this tutorial we will also select Custom boot logo and Custom recovery logo.

When you click to select each custom logo option a dialog window will appear asking you to select the image. Locate the image you would like to use then press the Open button.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

*Remember the rules for boot logos are: RGB or Grayscale format with Alpha channel and dimension below 320x480. If you would like to use the iClarified ones they can be found here: Boot Logo, Recovery Logo

If you read the warning above and you would like to update your baseband to the 06.15 iPad version for unlock then check Install iPad Baseband. Click Yes when prompted to confirm your decision.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Click the Next button to continue
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Step Nine
Please plug your iPhone into the computer and make sure its OFF then click the Next button
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Step Ten
RedSn0w will now guide you through the steps to get into DFU mode. You can find more help with DFU mode here
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Hold down both the Home button and the Power button for 10 seconds.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Release the Power button and continue holding the Home button until RedSn0w detects the device.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Step Eleven
RedSn0w will then download the iPad baseband and your iPhone will now reboot
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1] How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Step Twelve
RedSn0w will now begin uploading the new RAM Disk and Kernel.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

Step Thirteen
Once this is complete you will be notified that RedSn0w is done. Click the Finish button. When your iPhone finishes rebooting (5 minutes or so) it will be jailbroken with Cydia on the SpringBoard.
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

If you have a newer iPhone 3GS and performed a tethered jailbreak you can use Redsn0w to help you boot back into your jailbroken device. Simply select Just boot tethered right now from the options window and click Next
How to Jailbreak and Unlock Your iPhone 3GS Using RedSn0w (Mac) [4.2.1]

If you need to unlock you can now follow this tutorial.

*As usual a big thanks to the iPhone Dev-Team for their hard work and contribution to the iPhone community.
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Comments (78)
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H1uams - October 27, 2014 at 5:22pm
Great instructions, best I had found as others took hours and did not work. Would suggest using redsn0w 0.9.14b2 and not the most upto date. Many thanks.
Marlon - July 29, 2013 at 3:26pm
Make sure to remove your sim card if you have one (I'm running Iphone 3gs new bootroom at&t) I'm a newb but I noticed that this was the only way I could get the jailbreak to work. Also have a question: If you reboot your phone untethered, do you loose all your jailbreak data?
Luigi Pirandelo
Luigi Pirandelo - November 26, 2011 at 11:14am
Hello everyone! I have a question and I hope you can help me. I have an iPhone 3GS, 4.2.1, 05.15.04 and I want to unlock it. I am planning to backup all my files with iTunes, then jailbreak it and the unlock it with RedSn0w, following this tutorial. I understand that this will change my broadband to 06.15 and the risks. My question: If anything goes wrong with the Jailbreak and I need to reinstall the stock firmware using the iTunes backup, will I be able to bring back my iPhone to the same state before jailbreaking it? Thanks a lot for your help! :-)
Thomas - February 3, 2011 at 10:49am
Hi. I have tried this several times with no luck. Couple times I got a failed to enter DFU massage, but I mostly get unexpected error and instructions to reboot and try again. What am I doing wrong here?
lulu - February 1, 2011 at 12:52pm
DONE! Thanks folks. JB/unlock a friend's 3GS which he inherited from a pal. Works like a charm!
Symona - October 26, 2011 at 2:42am
Clear, inorfmtaive, simple. Could I send you some e-hugs?
verdao - January 25, 2011 at 4:24am
I hope this isn't a repeat question, but please help. I have a 3GS, old bootrom, 05.11.07 baseband. I installed 4.2.1 using pwnage tool and the minimal bundle. Now when I attempt to jailbreak with redsn0w, but redsn0w either crashes when I try to put the phone into DFU mode when prompted by redsn0w or, if I put the phone into DFU mode before starting the process, it says it's encountered an unexpected error. Any advice or help very much appreciated.
David - January 18, 2011 at 3:01pm
NEED HELP!!! I followed the tutorial. At the very end (jailbreak happening directly on the iPhone), I have the iPhone restarting with the message in iTunes "the SIM Card inserted in this iPhone does not appear to be supported". The only deviation I did from the tutorial is that I downloaded redsn0w_mac_0.9.6rc8 & selected the option "activate". What should I do next (apart from throwing my iPhone away)?
ScooterComputer - January 11, 2011 at 3:43pm
Just wanted to give some updated info for those who might be asking. I was hesitant to do the 4.2.1 update because I could not find ANYWHERE that talked about the 4.2.1 Baseband Version Check as it pertained to the 3GS, or the stability of the 4.2.1 "minimal" bundle for the 3GS released by the Dev-Team. #1 The 4.2.1 Baseband Version Check must not affect the 3GS (old bootrom) because I am successfully running 4.2.1 with 5.11.07 without problems! I would still like to see this version check detailed more than it has, what models it affects, etc, but it is NOT inhibiting my usage of 4.2.1. #2 I have been running 4.2.1 with the "minimal" bundle on my Old Bootrom 3GS--jailbroken--for several weeks. It has been rock solid. Battery life is nearly as good as I remember under 3.1.2. I have had no WiFi, Bluetooth, GPS, or other problems. My phone has locked up/rebooted one time, and who knows why that might have been; I've seen that happen to non-jailbroken devices. And I even restored my 3.1.2 Backup to the phone…which is not normally a good idea. Overall, for experienced (not necessarily guru-level) users who can read and figure out their way around PwnageTool and Redsn0w, I would absolutely suggest doing this update. Especially if you're down in the 3.1.x's with older baseband. BUT STAY AWAY from 6.15 and stock 4.2.1!
Ankit - December 23, 2010 at 12:40am
hey i tried using this method for jailbreak my iphone 3gs on 4.2.1. everything goes on smooth it got restored also but when i use the redsnow thing it says it has worked good but after tht everytime the cydia is not loaded completely and it doesnt operate. kindly help
dubbs - December 29, 2010 at 5:07pm
Same problem here. Cydia flashes and nothing happens. Iphone 3gs, 4.2.1, 05.15.04-6.4_M3S2
lightgale - January 27, 2011 at 12:53pm
ok, tried a jailbreak for a factory unlocked/neverlocked iPhone 3GS everything went smooth, now I see the apple logo and the spinning wheel frozen, and it just won't boot... wtf? So this is the way to brick an iPhone? pfff, what a luck to learn from my mistake... is there any solution? It just vibrates and on the screen there is the apple logo and the frozen wheel... :-( tried checking the tethered boot, I have the pineapple logo instead... still the phone is bricked... am I that stupid?
lightgale - January 27, 2011 at 1:46pm
ok, it looks like it was my bad, as I had to perform a tethered boot, so I miscalculated the week of manuf. tethered boot it is now, but it was painfully slow...
ann - December 21, 2010 at 3:04pm
just tried to do the restore with custom ipsw in itunes, and after extracting it, it tries to contact the apple server to verify the update, but then fails. tried it last night, and again today, and got the error message both times. didn't itunes just have a minor update? does this break the jailbreak? i'm on itunes 10.1.1 ...
Airwalker - December 20, 2010 at 12:36pm
HELP!! Just tried to jailbreak my iPhone 3GS, 4.2.1, 05.15.04, week 34/09) following the instructions above using redsn0w 0.9.6b5. The device does not reboot, instead hangs at "Please wait while your device is being processed. Waiting for reboot". What's going on? Helpful hints very appreciated! Tks
Airwalker - December 27, 2010 at 9:21am
Sorry, realised that I used the 4.2.1 version for the iPhone 3G instead for the iPhone 3GS. Problem solved!
Randall Murry
Randall Murry - December 18, 2010 at 10:00am
im using this to jailbreak and unlock but when it gets to the screen after all the baseband downloads....it sticks on- "please wait while your device is being processed" "waiting for reboot" now what? and i can't turn phone back on, its just black
Yhsay - December 16, 2010 at 11:56pm
Hi, I have a 3GS jailbroken and unlocked using BlackRa1n and its currently on OS 3.1.2 and baseband 05.11.07 I am a bit confused on this tutorial, so please help me with these questions 1. Do I need to install both redsnow and ultrasnow 1.2 to get an unlocked 4.21 2. Do I have to first uninstall BlackRa1n on my phone to restore it to any previous condition or should I just download 4.21 , use first redsnow and then ultrasnow? 3. Do I need to upgrade my baseband to 06.15 or should I let my baseband remain at 05.11.07? Rgds Yhsay
thomas - December 17, 2010 at 12:58am
thanks you
Alexandre - February 17, 2011 at 7:43pm
I,m with the same questions. I have exact situation, but I didnt see de answer. How did you make? Thank you
noburg - December 14, 2010 at 8:37pm
Used this method on 32GB 3GS FW 4.1 with iBoot-359.3 Upgraded to 4.2.1 via itunes then followed above steps, all good, no dramas. Did not upgrade my baseband, assuming because i said 'No' to the 'Is it new version' question. Thanks a lot to the author.
edieamien - December 3, 2010 at 2:49am
help any website to download custom firmware 4.21 ?...........
dan - December 1, 2010 at 12:57pm
just jailbreaked my 3gs new bootrom, but after unlocking with ultrasn0w, stuck on apple logo when rebooting, now my 3gs stuck in recovery mode, can't restore it or kick it with tinyumbrella, any ideas ?
dan - December 2, 2010 at 11:11am
problem solved! just downgraded it with tinyumbrella
tony_cicero - January 13, 2011 at 3:10am
Hi Dan, how exactly did you restore or downgrade ur iphone 3gs using tinyumbrella? i saved my shsh files all the way from 4.0.2. but find that even when i run the tss server thing whilst highlighting which version i want to be restored to it just starts the service & 20mins later nothing has happened. please let me know how you managed as i'm now stuck on 4.2.1 baseband 05.15.04_6.4(M3S2) - new bootrom version week 91 i guess as message had popped up the 1st time saying this is a new version of the iphone 3gs - if that helps. need to upgrade baseband to 06.15 to unlock but redSnow needs me to put phone into DFU mode which isn't possible when in restore mode, or is it???
ravichandra - November 30, 2010 at 10:24pm
When can we expect jailbreak and unlock for Iphone 4 with 2.10 baseband.
Jeffd - November 30, 2010 at 6:41pm
Is there going to be a tutorial on how to do this without upgrading the baseband? I am on 4.0.1 BB 5.13.4 unlocked. I see there is a way to maybe upgrade to 4.2.1 without changing my baseband.
Lukas - November 30, 2010 at 3:25pm
I have updated my BB to 06.15 and restore my iphone 3GS from backup after I unlock it via ultrasn0w in cydia. But the battery life was bad, so I decided to restore my iphone but not from backup but it gives me a (21) error code. Can someone help me, and say me how could I restore my 3GS(6.15) to 4.2.1. ?? ..
Satz - November 30, 2010 at 9:01am
Unable to install cracked apps on to the iphone 3gs. followed all the instruction and cydia is working but not able to install the cracked apps. can anyone help me with this pls
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