After the official release of iOS 5.1 by Apple, the iPhone Dev Team was fast enough to release the updated version of redsn0w. This latest version allows you to preserve iPhone’s baseband & update it to iOS 5.1. Baseband preservation allows you to use Gevey sim or ultrasn0w and use your iPhone 4 & iPhone 3Gs with any GSM carrier worldwide. After updating to custom iOS created by redsn0w, you can also jailbreak iOS 5.1. The jailbreak is currently tethered.
Gevey sim works on iPhone 4 running iOS 5.1 with preserved baseband.
How To Preserve Baseband & Update your iPhone 4/3GS to iOS 5.1 using redsn0w 0.9.10b6?
Step 1: Download iOS 5.1
Step 2: Download redsn0w and launch it
Step 3: Click Extras
Step 4: Click Custom IPSW & then browse for iOS 5.1 IPSW that you downloaded in Step 1
Step 5: redsn0w will start patching iOS 5.1
After creating custom firmware, redsn0w will save the custom IPSW in the same folder where your original IPSW is present. The name of the custom iOS file will start with NO_BB.
Step 6: Now, click Pwned DFU option under Extras menu. At this point, plug in your iPhone 4 or iPhone 3GS to PC/Mac and turn it off. And then click Next in redsn0w.
Follow the instructions on the screen to put your iPhone in Pwned DFU mode.
Step 7: Once your iPhone is in Pwned DFU mode, launch iTunes & press Shift + Restore (Windows) or Select + Restore (Mac) and point iTunes to the custom iOS 5.1 created by redsn0w.
After successful restore, the baseband on your iPhone will be preserved & you can use Gevey sim or ultrasn0w to unlock it.
After preserving the baseband, you can jailbreak iOS 5.1 & install Cydia on your iPhone 4 or iPhone 3GS.
If you’ve any queries or difficulties, feel free to ask below.
{ 2 comments… read them below or add one }
Thank you SO MUCH for this step by step!
You are awesome!
I searched and found a lot of tutorial but I used yours – and let me say, the best one, with clearly informations. It was my first update, using gevey and coming from 4.3 to 5.1 preserving baseband. Used redsnow and everything went as expected. Even iTunes worked like a charm and restored my apps/photos/etc backup.
Thank you again Mahesk! Keep up with the good work. I have signed your newsletter, your site have the best articles about iPhone.
Greetings from Brazil.
Hi again,
I noticed today that my iPhone is not showing contact names when receiving calls neither on received SMS.
Have any hints? I read that if I jailbreak it and edit a file, I can make it work here in Brazil. But is there any other way to do it, without jailbreaking?
Thanks!