Let’s say you recently updated your iPhone to iOS 4.2.1 and for various possible reasons, you are already regretting this move. It is possible to downgrade your iPhone 4.2.1 to a previous iOS, but for this, you need to have your SHSH blobs on file for the iOS you want to downgrade to. To be completely clear, if you don’t have your SHSH blobs on file for the iOS you want to downgrade to, you will n
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