The invention relates to a process for releasing the access to a computer system or to a program for a user via a terminal (2) without software having to be installed solely for this purpose on the terminal (2). A data connection is established between a portable data carrier (1) of the user and the terminal (2). An authentication of the user is performed by the portable data carrier (1). If the authentication is successful, an access code is made available by the portable data carrier (1) for releasing the access to the computer system or to the program for a transmission via the data connection.