Client device and server device for safe unlocking functions of a client

It is proposed to a client device for safe unlocking functions of a client. The client apparatus includes a storage unit for storing a plurality of activation keys, each unlock key is defining at least one function of the client and associated with a password, a receiving unit for receiving a password from a server, and a processing unit for comparing the plurality of activation keys with the received password for selecting the activation key, which is associated with the received password, and for enabling at least one function of the client that is included in the selected product key on. Furthermore, proposed a server device for providing a password for a client device and corresponding methods. The proposed client and server devices, it is possible in advance to store service keys in clients that can be activated only by a password from the server device, however. In this way, secure features of the client can be released.