Abstract: A vending-type machine for goods and/or services, and a method of operating the same. The machine has a computer that is connected via a data communication line with a central computer located in a central office. In order, despite the absence of an intermediate cash box for bills received during an interrupted payment process, to be able to protect against fraudulent refunds for equivalent values on vouchers issued by such machines, a plain language as well as machine-readable coded data entry is printed on the voucher, with this data entry, in addition to the value of the bill, also containing the location indication of the particular machine, and the actual date and time in seconds. This data entry is entered in a data-protected memory of the machine, and is entered via the data communication line in a data-protected memory of the central computer.