With release of latest OS from Apple many iPhone users thought about updating their iPhone to iOS 5.1. But you may think twice before updating, because after that you will lose your jailbreak and unlock. Jailbreak iOS 5.1 you can here (tethered) or use Step 7 to do it quickly. But what about unlock?
That's why I decided to show you how to update iPhone to iOS 5.1 preserving old baseband (unlockable). So if you have your iPhone unlocked and want to keep your old baseband for future unlock after updating then this post is just for you.
Before we start read this important info:
Step 6. Now RedSn0w tool will customize the IPSW for you to preserve old baseband.
Step 12. Select “NO_BB” IPSW which has been customized.
Step 13. Connect iPhone and enter DFU Mode in RedSn0w like in Step 9 and wait for success entering.
Step 14. Open iTunes and holding down Shift/Option (Win/Mac) click Restore and select custom IPSW “NO_BB”.
Step 15. After Restoring process iTunes will reboot iPhone automatically.
That’s all. You have just updated your iPhone to iOS 5.1 preserving old baseband for future unlock. This is very important to save your old baseband because it is so hard in our days to perform iPhone unlock and use it with any Sim card.
If there will be some problems then tell me about it in the comment section below.
Before we start read this important info:
- This method will not unlock your iPhone
- This method preserve iPhone 4 and 3GS basebands
What do you need
Download updated Redsnow 0.6.10b8b here Download iOS 5.1 here Download iTunes hereUpdate to iOS 5.1 Preserving Old Baseband
Step 1. For best use create a folder where you will download RedSn0w tool and iOS firmware. Step 2. Unzip RedSn0w and Run as administrator .exe file. Step 3. Now after opening RedSn0w select Extras. Step 4. Select “custom IPSW”. Step 5. Now open your just downloaded iOS 5.1 firmware.
Step 6. Now RedSn0w tool will customize the IPSW for you to preserve old baseband.
Jailbreak iOS 5.1 Using RedSn0w
Step 7. Now enter Pwned DFU mood (Extras => Pwned DFU). Step 8. Make sure that your iPhone is connected to PC and is turned off and click Next. Step 9. Now you need to enter DFU mood following instructions on RedSn0w screen. It is not simple method so go here to learn how to do it easy. Step 10. After entering DFU mood open iTunes. Step 11. In iTunes choose your iOS gadget from the list on the left and holding down Shift/Option (Win/Mac) click Restore
Step 12. Select “NO_BB” IPSW which has been customized.
Step 13. Connect iPhone and enter DFU Mode in RedSn0w like in Step 9 and wait for success entering.
Step 14. Open iTunes and holding down Shift/Option (Win/Mac) click Restore and select custom IPSW “NO_BB”.
Step 15. After Restoring process iTunes will reboot iPhone automatically.
That’s all. You have just updated your iPhone to iOS 5.1 preserving old baseband for future unlock. This is very important to save your old baseband because it is so hard in our days to perform iPhone unlock and use it with any Sim card.
If there will be some problems then tell me about it in the comment section below. 
