How to upgrade your iPhone to iOS 5 while preserving the Baseband for Unlock (Windows)

Having an unlocked iPhone is what almost every iPhone users wanted to have. This is because you can switch to any carrier any time you want. Sn0wbreeze is the best tool to use if you are running on a Windows OS machine. With Sn0wbreeze, you can preserve the baseband of your iPhone while upgrading to iOS 5 if you are from iOS 4.x.x.

The following steps will upgrade your iPhone to iOS 5 and at the same time will preserve your baseband for unlocking purposes: (Note: can be used with iPhone 4/3GS/3G)

1. Download Sn0wbreeze 2.8 Beta 8.
2. Launch Sn0wbreeze and click OK and the blue arrow below.
3. Drag to the gray box on Sn0wbreeze the iOS 5 firmware but make sure that the firmware for your device is correct.
4. After verifying that the firmware is correct, click the blue arrow below and click on “Baseband Preservation Mode”. Click NEXT.
5. Sn0wbreeze will then start to build your custom firmware. After finished, the custom firmware will be saved to your desktop. Verify and click OK.
6. Start your iPhone to DFU mode: Hold ‘Home+Power’ buttons simultaneously for 10 seconds, release Power button while continue holding the Home button for another 10 seconds.
7. On the DFU Pwner screen in Sn0wbreeze, click START.
8. “iREB” will start and will place your iPhone in Pwned DFU Mode. Close out Sn0wbreeze completely after clicking the confirmation screen.
9. Launch iTunes so it will recognize that your iPhone is in Recovery mode. Click OK.
10. Hold ‘Shift+Restore’ and browse to the newly created firmware in your desktop.
11. Wait for the Restore process to finish and you should have the same unlockable baseband.

Enjoy having an iOS 5 while preserving your baseband!