Jailbreak iOS 5 Preserving Baseband

Jailbreak iOS 5 Preserving Baseband
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In this tutorial, I will guide you on how to jailbreak your iPhone 3G or iPhone 4 with iOS 5.0 firmware without updating the baseband. This tutorial is essentially for iPhone 3G and iPhone 4 users who have a lower baseband version on their iPhone and want to preserve unlock while moving to the new iOS 5.

Note: This tutorial is for both Windows and Mac users. Windows/Mac users may use the new RedSnow 0.9.9b7 version. However, the Windows version of RedSnow doesn’t have the option to prepare custom ipsw files and users will have to wait until a newer version is out, which contains the option to create custom firmware for iOS 5 from Windows.

This is a tethered jailbreak that means whenever you turn your iPhone off and on, you will need to connect it to the PC, run redSnow and only then will you be able to boot it.

Before performing the jailbreak, make sure you save your iPhone SHSH blobs – they will help you in the future if you decide to go back to a lower firmware version.

Step-by-Step Instructions

Step 1: Before you start with the jailbreak process, download the following software:

RedSnow 0.9.9b7 for Mac/Windows

iPhone 4 iOS 5.0 Firmware

Latest version of iTunes

*links available in Download Section below

Step 2: Make sure your iPhone is connected to the computer. Now, launch the RedSnow application. On the RedSnow welcome screen, press the Extras button to continue.

Step 3: In order to jailbreak without updating the baseband, you will have to build a custom firmware file using Apple’s iOS 5. From the available options, press the “Custom IPSW” button to continue to build a custom firmware file for your iPhone.

create custom ipsw from redSnow

Step 4: You will now be asked to select the iOS 5 firmware file that you just downloaded. Select the file and click open. RedSnow will now automatically build a custom firmware file for your iPhone 4.

Once the process is complete, redSnow will notify you with a screen that shows the location where the custom ipsw file was saved along with a self explanatory note that says, “Do not use the custom firmware file. Use the file whose name begins with NO__BB”.

custom ipsw for iOS 5 created by redSnow

Click the Ok button to continue.

Step 5: Once you are back at the extras menu, press the Pwned DFU button to continue with the jailbreak process using custom iOS 5 firmware file.

enter pwnded DFU mode to restore custom iOS 5

You will now be asked to put your iPhone into DFU mode. Follow the link here.

Step 6: As soon as redSnow detects your iPhone, it will use the LimeRa1n exploit to prepare your iPhone for update to the custom firmware file. Once the process is complete, it will show you a message window that says, “Your iPhone is now in pwned dfu mode and ready for iTunes to accept custom ipsw file.”

Step 7: Launch iTunes, while your iPhone is connected to the computer. Cancel the message, if you are asked to update to the new iOS 5. Instead, hold down the Option key and press the Restore button.

restore iPhone with iTunes

Finally, select the custom firmware file whose name starts with “NO_BB” to restore your iPhone with the custom firmware file.

iTunes will now restore your iPhone using the custom ipsw file.

To jailbreak your iPhone 4 with a custom iOS 5 firmware file, follow steps 4-6 from this guide here. Once you complete the steps carefully, you will have a jailbroken iPhone running the new iOS 5.

Since, this is a tethered jailbreak; you will have to use RedSnow to boot your iPhone.

Step 1: Make sure your iPhone is connected to the computer. Now, launch RedSnow and press the Extras button to continue.

redSnow extras

Step 2: From the list in the Extras menu, press the “Just boot” button to boot your iPhone. You will now be asked to put your iPhone in DFU mode. Once in DFU mode, RedSnow will upload the LimeRa1n exploit to make sure that your iPhone reboots.

Download Section

RedSnow 0.9.9b7 (MAC) - https://sites.google.com/a/iphone-dev.com/files/home/redsn0w_mac_0.9.9b7.zip?attredirects=0&d=1

RedSnow 0.9.9b7 (Windows) - https://sites.google.com/a/iphone-dev.com/files/home/redsn0w_win_0.9.9b7.zip?attredirects=0&d=1

iPhone 4 (GSM) iO.S 5.0 - https://appldnld.apple.com/iPhone4/041-8358.20111012.FFc34/iPhone3,1_5.0_9A334_Restore.ipsw

iPhone 4 (CDMA) iO.S 5.0 - https://appldnld.apple.com/iPhone4/041-9743.20111012.vjhfp/iPhone3,3_5.0_9A334_Restore.ipsw


  • Images Credit: RedSnow application screenshots by RedSnow.
  • Source: Author’s own knowledge.
  • iTunes screenshots by Apple.