I have downloaded the IOS 17 beta package from the Apple Developer download site. I am having issues installing it on an iPhone 13 mini. The iPhone is in Developer mode but it still errors out when restoring the image. What is the procedure to accomplish this downgrade?
Degrade IOS 18 beta to 17 beta to test legacy iOS
The iOS 17 downloads available through the More Downloads section of the Apple Developer website are for the iOS 17 simulators. You can only install those for use with Xcode, they cannot be installed to a device.
— Ed Ford, DTS Engineer
Ed addressed your specific question, but I want to address about the big picture…
It seems like your goal is to downgrade an iOS device from a newer version of iOS to an older version. There’s no supported way to do that [1] on iOS or any of its ‘child’ platforms [2].
Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"
[1] The only exception being during the beta cycle of a new OS, where it’s possible to erase and device and install the most recent non-beta OS.
[2] It is possible to do this with macOS.