If one of the firmware is no longer signed, meaning Apple has removed its signature, then the downgrade process will fail. When you use iTunes to switch between two iOS versions, Apple will use iTunes to find the SHSH Blobs to determine if you are downgrading to a signed iOS firmware. It's not possible to downgrade to an unsigned iOS version without an SHSH Blobs. When an iOS user tries to restore their device, one of the functions of SHSH Blobs is to assist Apple to determine whether a signed IPSW firmware file is being used. SHSH Blobs is a part of Apple's digital signature system, which is a piece of code and embedded in each iOS firmware for each iOS device. Part 4: How to Downgrade iOS with WooTechy iMaster? Part 3: How to Install Unsigned IPSW with SHSH Blobs? Part 2: Is it Possible to Downgrade to Unsigned iOS without SHSH Blobs?

How to downgrade to unsigned iOS? Is it possible to downgrade unsigned IPSW without SHSH Blobs? How to install unsigned IPSW without SHSH Blobs? You will find all the answers in this article! Without further ado, let's get started!

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