The method involves connecting a communication unit (10) with an interface (11) of a data processing unit (20) by another interface (21). A part of operation systems is transferred to the data processing unit over the interfaces by the communication unit after activating the data processing unit, where the interfaces are a part of a USBsystem. A personalized adjustment of the operating systems is transferred to the processing unit by the communication unit. A communication link (51) is established in a mobile network (50) by communication elements (12). Independent claims are also included for the following: (1) a computer program product for executing a method for operating a data processing unit (2) a communication unit comprising an identification element.
