The error message "An administrator has restricted sign-in" indicates that the account has been intentionally blocked from ...

The update patches the OS against an attack on USB Restricted Mode, which Apple first implemented in devices with the release of iOS 11.4.1 in 2018, to prevent attempts to bypass device passcodes ...

USB Restricted Mode is that feature where you have to enter your iPhone or iPad passcode when you connect it to a computer or other USB device with a data connection, saying you “trust” that ...