A postage meter mailing system utilizes a meter vault (24) operated under the control of a microcontroller (44) mounted in a secure housing. The microcontroller (44) of the meter vault (24) has a communication device (43) for receiving and transmitting data messages and non-volatile memory (40, 41) for storing program data and other data. A printer (27) is utilized for printing a postage indicia. The printer (27) operates under the control of a microcontroller (66) mounted in a secure housing. The microcontroller (66) of the printer (27) has a communication device (63) for receiving and transmitting data messages and non-volatile memory (61, 62) for storing program data and other data. An interface (23) provides a communication path between the meter vault and the printer. The non-volatile memory (40, 41) of the meter vault has stored therein a program version number for identifying the control program version. The non-volatile memory (61, 62) of the printer has stored therein a software update number for identifying associated meter vault programs which utilize the update software. Upon system start-up, the print head microcontroller (60) requests the meter vault microcontroller (44) to transmit the control program version and number and determines whether the control program requires the update software and if so transmits the update software.