Here is a step by step guide on how to Jailbreak and unlock your iPhone 3GS or iPhone 3G running iOS 4.2.1. Follow all the steps below to successful jailbreak and unlock your device using RedSn0w 0.9.6b5. 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.
Those of you having tether jailbreak can untether your iOS 4.2.1 here. After it you won’t need RedSn0w every time you reboot your device. (link)
Note for Unlockers
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.
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).
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.
Lets get started
Things you need
- RedSn0w 0.9.6b5
Select your model
- iOS version 4.2.1 for iPhone 3GS
- iOS version 4.2.1 for iPhone 3G
1 ) Create a folder on your desktop Download RedSn0w and iOS 4.2.1 (links above) and place the files in ‘Pwnage’ folder you just created called Pwnage
2) Download RedSn0w (extract it) and iOS 4.2.1 (links above) and place the files in ‘Pwnage’ folder you just created
3 ) Connect your iPhone to the computer and launch iTunes and select your iPhone from the list of devices, now hold shift button and click on the Restore button.
Note: If you are already on iOS 4.2.1 skip this step.
4 ) Navigate to the Pwnage folder on your desktop and select the 4.2.1 firmware ipsw. Click the Choose button to continue.
Note: If you are already on iOS 4.2.1 skip this step.
5 ) 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.
Note: If you are already on iOS 4.2.1 skip this step.
6 ) Now open the Pwnage folder on your desktop and launch the redsn0w application from the redsn0w folder we extracted earlier.
7 ) Once RedSn0w opens click the Browse button
8 ) Select the 4.2.1 firmware ipsw we placed in the Pwnage folder on our desktop then click Open.
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 an untethered jailbreak on the older model.
Once the firmware gets verified click the Next button to continue.
9 ) Let RedSn0w to prepare Jailbreak data.
10 ) From this window you can select the jailbreak options you would like make sure Cydia is selected.
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.
11 ) Click the Next button to continue
12 ) Plug iPhone into the computer and make sure its OFF then click the Next button.
13 ) RedSn0w will now guide you through the steps to get into DFU mode. Follow the instructions displayed on your Screen.
14 ) Your iPhone should now reboot
15 ) RedSn0w will then begin uploading the new RAM Disk and Kernel.
16 ) Once uploading is complete you will be notified that RedSn0w is done. Click the Finishbutton. When your iPhone finishes rebooting (might take 5 minutes or more) it will be jailbroken with Cydia on the SpringBoard.
17 ) Done!
*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 nowfrom the options window and click Next.
You can unlock your device using this guide (Link)
For any help regarding the jailbreak process please leave a comment below, we are here to assist you.