Apple has ceased signing iOS 17.6.1, preventing downgrades from iOS 18+

Apple launched the official version of iOS 18.0 for all supported iPhones last week, with many devices automatically updating the system overnight during charging. This automatic update process is why the new version of iOS quickly achieves widespread coverage after its release.

The iOS 18.0 update brings numerous improvements to the user interface, including customizable home screens, a brand-new control center, a redesigned photos app, support for RCS rich media messaging, and call recording capabilities.

However, for users who have already automatically upgraded to iOS 18.0, downgrading is no longer possible. Apple has disabled online verification for iOS 17.6.1, making it impossible to restore using IPSW firmware.

The only exception is the iPad Pro based on the M4 chip. Due to potential bricking issues after updating to iPadOS 18.0, Apple had to temporarily withdraw this version and release iPadOS 17.7 IPSW firmware for affected iPads. This allows users to temporarily restore their device's functionality through firmware reinstallation.

For those who have joined the Apple Beta Program and are using the iOS 18.1 Beta, it is still possible to downgrade to iOS 18.0. Since the verification for iOS 18.0 has not been closed and iOS 18.1 is still in beta, Apple allows downgrading from the latest beta version to the official release.