As promised in our previous post, here is the step by step guide to unlock iOS 4.2.1 on iPhone 3G, 3GS using Reds0w and Ultrasn0w.
First we will update the baseband to iPad 06.15 and jailbreak the iPhone with Redsn0w. After the device is jailbroken, we can use Ultrasn0w from Cydia to unlock the device. Find the complete guide after the break.
Please read these instructions and warnings before you start the actual process:
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).
Step 1: Download iOS 4.2.1 for your idevice.
Step 2: Download iTunes 10.1 and install it on your PC.
Step 3: Back up all the contents on your phone before you start the actual jailbreak process.
Step 4: Save the SHSH blobs if you are still on iOS 4.1 or below version. !very important
Step 5: Update/restore your device to iOS 4.2.1 via iTunes.
Step 6: Download Redsnow 0.9.6 beta 4 and run it.
Step 7. When asked for iOS firmware, point the redsn0w to iOS 4.2.1 downloaded in first step.
How to Unlock iPhone 3G(S) on iOS 4.2.1 with Ultrasn0w and Redsn0w [Guide] redsn0w ultrasn0w 2
When you receive a pop-up message, click on Yes to confirm the baseband change.
How to Unlock iPhone 3G(S) on iOS 4.2.1 with Ultrasn0w and Redsn0w [Guide] redsn0w ultrasn0w 1
Step 8: Click on next and select “Install Cydia” and “Install iPad Baseband” options. Optionally you can also select any other option available for your idevice.
How to Unlock iPhone 3G(S) on iOS 4.2.1 with Ultrasn0w and Redsn0w [Guide] unlock redsnow1
Step 9: At this step make sure that your phone is switched off and plugged into the computer. Follow the onscreen instructions to put the idevice into DFU mode.
Step 10: Let Redsn0w do its work. Once completed your phone will restart and you will find it jailbroken on iOS 4.2.1.
Now if you have iPhone 3GS New bootrom you will have to connect it with Resnow and select the “Just boot tethered right now” option to get the jailbreaked state on every boot.
How to Unlock iPhone 3G(S) on iOS 4.2.1 with Ultrasn0w and Redsn0w [Guide] RedSn0w Boot Tether
Downloads:
* Download iOS 4.2.1 for your idevice
* Download iTunes 10.1 for Win and Mac OS X
* Download Redsn0w 0.9.6 beta 5 for Win and Mac
Note: Windows 7 or Vista users often need to use XP or 98 compatibility modes when launching redsn0w (right-click).
How to Unlock with Ultrasn0w 2.1:
After your device is jailbroken using the above mentioned procedure, open the Cydia App and search for Ultrasn0w. Install it and reboot your device. Your device is now unlocked.
Disclaimer: This guide is for educational and testing purpose only. This site will not be responsible for any type of damage. Use it at your own risk.