Abstract: In methods in the transmission in a data communications network of arbitrarily formatted files between a sender (1) which represents an information provider and one/or more receivers (8) which represent users, a network server (5) is used in the transmission, the transmission itself taking place substantially transparent to both sender (1) and receiver (8). Before the transmission, a file which shall be transmitted is compression-coded, whereafter it is transmitted packet-divided via the server (5) to the receiver (8). In the transmission an already compression-coded file is subjected to a processing specific for one or more users and/or one or more specific application either in the server (5) or in the receiver (8) or both, without any effects on the transmission as such. Software used for the processing can be stored either at the sender (1), server (5) or receiver (8) and possibly downloaded automatically to the processing location.