May 31, 2012 by Abhay
This is a very useful method for user’s with carrier unlocked iPhone’s and for those who wish to upgrade their device to a newer iOS, preserving their unlockable baseband. Other’s can also use this method if they wish to stay on their current baseband.
You will need:
1. Latest version of redsn0w.
3. Custom Firmware File (.ipsw)
*Latest firmware can be downloaded from the following website : “www.felixbruns.de/iPod/firmware/”
Here’s how to go about it :
1. Launch redsn0w (Right Click, Run as administrator) and click on Extras.
2. Click on Custom IPSW under the Extras Banner.
3. Find and select the custom firmware file (.ipsw), which you had downloaded in the beginning and click on Open.
4. Wait for redsn0w to complete creating your custom firmware file.
Once it is done, you will see another .ipsw file in the same folder from where you had selected the custom firmware with a NO_BB prefix to the file name.
You will get a message saying “Custom IPSW created” and it will ask you to enter the “Pwned DFU” mode.
5. To enter the Pwned DFU mode, simply open redsn0w again and go to Extras, and click on Pwned DFU.
6. Before clicking on Next, make sure that your device is both turned off and plugged in to the computer.
7. Follow the on-screen instructions to put your device in DFU mode.
8. Once you are in DFU mode, the screen of your device will go blank and your computer will indicate that a device has been connected via USB.
9. Open iTunes, it will show that a device had been connected in Recovery Mode.
Select your device, now hold the Shift key and click on Restore.
10. A window will pop-up asking you to select the Custom firmware file.
Select the one which you had created using RedSn0w and make sure that you select the custom firmware file with the prefix NO_BB, else you will end up updating your device to the stock firmware which will also update your baseband.
11. Wait until iTunes restores your device to the custom firmware. This process may take up to 10 minutes.
Congratulations! Your phone is ready to use now! Enjoy your new firmware.
*Please note that your device will not be jailbroken after this process. To jailbreak your device running on iOS 5.1.1 please follow our step-by-step guide – http://thebudcloud.com/jailbreak-ios-5-1-1-untethered/
*If you get an error while restoring with itunes, you may use this guide to fix it – http://thebudcloud.com/itunes-error-3194/
*If you are running iPhone 3Gs on the SPECIAL iPAD BASEBAND 6.15.00, please go through this important piece of information by the Dev-Team.
During the new setup screens you see when you start iOS5 for the first time, you’ll be asked about Location Services. Be sure to select “Disable Location Services” when asked! Later on in the setup, you’ll have the chance to turn on Location Services again when asked if you want to use “Find my iPhone”. It’s fine to turn it back on at that point, if that’s your desire (or you can always go in and enable it in Settings.app).
Also, some iPhone3GS users with the 06.15 baseband may have tried to install iOS5 using a stock IPSW (even though you should never ever try to use a stock IPSW if you’re an ultrasn0w unlocker). If you did try this, your baseband is probably in an inconsistent state, and you’ll need to reflash the 06.15 baseband again (using redsn0w). Be very careful if you use redsn0w to reflash the iPad baseband — don’t interrupt the process! And please avoid using stock IPSWs in the future.
Unlockers should never go near stock IPSWs.
You can also use sn0wbreeze for this purpose.
I hope this post helps you! Keep following for more information and tutorials!