A diagnosis apparatus is disclosed that is able to promote productivity of a diagnosis of the target program which may be for an image forming apparatus such as a printer, a copier, or a fax. The diagnosis apparatus uses a diagnosis program which acquires log information of a target program at runtime. The diagnosis program is sent to a situation where the diagnosis program is to be executed. Further, the diagnosis apparatus includes a memory unit configured to store correspondence data between the diagnosis program and program selection information, where the program selection information is used for selecting the diagnosis program. Also included is a selecting unit which selects the diagnosis program based on the correspondence data, a sending unit which sends the diagnosis program to the situation, and a receiving unit which receives the log information from the diagnosis program.