The operator terminal receives input of the terminal status of the recovery target terminal 10 from an operator, extracts a recovery item for recovering the terminal status of the recovery target terminal 10 and a recovery set value being a value recovered corresponding to the recovery item based on the input terminal status, and generates a recovery code at least including the recovery item and the recovery set value. The recovery target terminal 10 decodes the recovery code in response to input of the recovery code to acquire the recovery item and the recovery set value and executes a recovery process for the terminal status based on the acquired recovery item and the acquired recovery set value.