To prevent usage by unauthorized installation of a medical institution business support program for issuing a receipt recording a medical institution identifier proper to a medical institution.

A password issuing program issues a password by combining the information containing business office number. An installed program obtains the information containing the business office number and the password from a user when concluding install of a care business proprietor support server program, and generates a password by using the information containing the business office number, and in the case wherein the generated password and the obtained password are the same, the information containing the business office number is registered as authenticated information in an authenticated information management table. The care business proprietor support server program can be carried out in the only case wherein the authenticated information is set in the authenticated information management table.