A
data processing device including a
microcontroller and configured to communicate with at least one
remote system distributed on a network. The
data processing device and the
remote system are adapted to store a plurality of parameters identifying a user account belonging to a subscriber. The
data processing device comprises a one-
time parameter comprising the active account attached to the device designed for a one-time use, and a permanent parameter identifying an account attached to the data
processing device, the permanent parameter being deactivated. The one-time and permanent parameter are stored in the at least one
remote system, and the
microcontroller is programmed to: use the one-
time parameter to logon to the network when the data
processing device is switched on; and exchanges the one-
time parameter with the permanent parameter, upon successful logon to the network, the permanent parameter becoming the permanent active account. The first device and the at least one remote
system store a parameter identifying a current active account attached to a second data
processing device to replace, and upon successful logon to the network, a program automatically stored in the first device sends an activation request for exchanging the plurality of parameters from the old for the new one in the at least one remote
system, with the current active account being deactivated.