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Continue to ChatHow to Downgrade iOS 4.2.1 to iOS 4.1, 4.0.1 or iOS 4.0.2 — https://www.shoutpedia.com/downgrade-ios-4.2.1-to-ios-4.1-4.0.1-ios-4.0.2/
How to Downgrade iOS 4.2.1 to iOS 4.1, 4.0.1 or iOS 4.0.2 — https://www.shoutpedia.com/downgrade-ios-4.2.1-to-ios-4.1-4.0.1-ios-4.0.2/