A registry storage stores information of device configurations and device identifiers, on a per-device basis. A repository storage stores a correspondence between the device identifiers and device controllers which match the respective devices. A sub-plurality of the plurality of device controllers provide the same function, and are executed in the respective devices, by calling a common interface which is shared between the device controllers. At least one of the device identifiers which corresponds to one associated device is retrieved from the registry storage, a device controller which corresponds to the retrieved device-identifier is retrieved, the retrieved device controller is installed into a library and executed, and the executed device controller is uninstalled from the library.