A device management system comprising: a network adapter connected to a device, the device comprising a first component that comprises first storage means and is replaceable with a second component comprising second storage means; first certification means for certifying the device; identification information generating means for generating identification information for identification of the device certified by the first certification means; and second certification means for certifying the device after replacement of the first component with the second component, wherein the network adapter comprises: first common certification information acquiring means for acquiring, from the device, first common certification information stored in the first storage means, the first common certification information being shared with another device; first setting means for setting the identification information to the device; third storage means for storing the identification information; second common certification information acquiring means for acquiring, from the device after replacement, second common certification information (D103A) stored in the second storage means, the second common certification information (D103A) being shared with another device after replacement; and second setting means for setting the identification information stored in the third storage means to the device certified by the second certification means, after replacement, the first certification means certifies the device based on the first common certification information, and the second certification means certifies the device after replacement based on the second common certification information (D103A). a network adapter connected to a device, the device comprising a first component that comprises first storage means and is replaceable with a second component comprising second storage means; first certification means for certifying the device; identification information generating means for generating identification information for identification of the device certified by the first certification means; and second certification means for certifying the device after replacement of the first component with the second component, wherein the network adapter comprises: first common certification information acquiring means for acquiring, from the device, first common certification information stored in the first storage means, the first common certification information being shared with another device; first setting means for setting the identification information to the device; third storage means for storing the identification information; second common certification information acquiring means for acquiring, from the device after replacement, second common certification information (D103A) stored in the second storage means, the second common certification information (D103A) being shared with another device after replacement; and second setting means for setting the identification information stored in the third storage means to the device certified by the second certification means, after replacement, first common certification information acquiring means for acquiring, from the device, first common certification information stored in the first storage means, the first common certification information being shared with another device; first setting means for setting the identification information to the device; third storage means for storing the identification information; second common certification information acquiring means for acquiring, from the device after replacement, second common certification information (D103A) stored in the second storage means, the second common certification information (D103A) being shared with another device after replacement; and second setting means for setting the identification information stored in the third storage means to the device certified by the second certification means, after replacement, the first certification means certifies the device based on the first common certification information, and the second certification means certifies the device after replacement based on the second common certification information (D103A).