A method of accessing an image forming apparatus (IFA) or a multifunction printer (MFP) using a management device (MD) via a network, transmitting security information from the MD to the IFA, updating an original security configuration of the IFA with a new security configuration using the security information, using the new security configuration by the IFA, and confirming the new security configuration with the MD. After confirming, it is preferable the security information is deleted. Also, an IFA including a confirmation unit and a write protection unit for use with the method.