Abstract: A method for installing user software in a host system unit (Z) of an electronic control system of a construction machine, in particular of a road paver (F), the user software and, in addition, in some cases, parameter-base data, completely stored in an external removable storage medium (W) which is designed to be suitable for the coarse conditions in a construction machine. The removable storage medium (W) is attached to a data exchange port (12), which is connected to the host system unit (Z). The user software and, in some cases, the parameter-base data, are transmitted during a start of the system or when attaching the removable storage medium (W) into the host system unit (Z) for installation purposes or for updating purposes. The construction machine is characterized in that a data exchange port (12) is provided at, or within, an operator's console (B), which data exchange port (12) is connected to the host system unit (Z).