Here are the step by step instructions on how to downgrade iPhone Bootloader!
A Bootloader is a particular code that is executed when your iPhone is switched on. It carries out integrity checks on data and stops non-Apple or unsigned codes from being loaded onto the device. Two Bootloaders that you may have heard of are iBoot and baseband bootloader. These Bootloaders act as iPhone OS police that make sure that everything stays the way Apple Inc. wants. If a jailbreak program is not available on a certain Bootloader, you can downgrade your unlocked iPhone’s Bootloader and then jailbreak via Sn0wbreeze, redsn0w, BlackRa1n or QuickPWN.
Here’s how to downgrade your iPhone 4.6 Bootloader to 3.9 using ZiPhone program. But before we proceed keep the following in mind.
- To do this downgrade restore your iPhone to 1.1.3 and then unlock it.
- The slightest mistake while following this tutorial can render your iPhone inoperable. Be extra careful in following the instructions.
Even after knowing the risks involved in downgrading the Bootloader, why would users want to still want to go ahead with it? It’s because users can unlock 04.03.12 baseband on 3.9 Bootloader and have applications like Google Locator work on their iPhone. Moreover, 4.6 Bootloader needs a secpack of a newer version to allow users to do things with the 04.03.12 baseband whereas the 3.9 Bootloader requires the same secpacks.
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