Unable to update my iPhone 8 to iOS 17

You can upgrade an iPhone 8 to the latest release of iOS 16 – currently iOS 16.7.10.

About iOS 16 Updates - Apple Support

You cannot update an iPhone 8 to iOS 17. For the iPhone 8, which originally ran iOS 11, iOS 16 is the end of the line.

Your iPhone 8 can only be updated to iOS 16.7.10 and no further. You need an iPhone XR or later to run iOS 17. But keep in mind that all the iPhones that supported iOS 17 also support iOS 18, the most up to date software.

An iPhone 8, iPhone 8 Plus, or iPhone X isn't capable of 17 or above; they require an A12 or better CPU.

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