To automatically retrieve and browse registered electronic data by a retrieval key character string prepared according to received error information when a fault occurs in an external apparatus whose display function is limited and the error information is received.

When the error information is notified from the external apparatus, the retrieval key character string for retrieving the electronic data stored in an external memory device 11 is prepared (S42). Then, on the basis of the prepared retrieval key character string, the external memory device 11 is retrieved and the electronic data are acquired (S43, S44). Then, the electronic data retrieved for the external apparatus are outputted (S45).