PURPOSE: To rapidly execute fault analysis by displaying abnormal information generated in an information processing in operating at the time of starting a diagnostic program.

CONSTITUTION: When abnormality is generated in the information processor, a program starting means 30 reads out the diagnostic program 40 from a memory to start up the program 40. A log information analyzing means 44 automatically reads out log information obtained at the time of generating abnormality in the operating information processor and the cause of the abnormality from log information stored in a log file and analyzes the cause of the abnormal contents. A diagnostic program automatic execution means 45 selects a device to be automatically diagnosed based upon the analytical result of the means 44 determines a diagnostic method for the device and starts up a diagnostic program executing means 46. The execution result of the means 46 is displayed on a display by a diagnostic result display means 47.