An information processor has an older version program and a latest version program of the same application software installed thereon. The information processor includes: an older version detection unit that detects the older version program installed on the information processor; a path name modification unit that modifies a first path name of a file storing the older version program to a second path name if the older version detection unit detects the older version program; and a start program file generation unit that generates a start program file storing a start program. The start program file generation unit generates the start program file as a file having the first path name, after the path name modification unit executes the path name modification.