You need to grant read and write permission on directory to user for taking backup.(Assuming that you have all the rights)
GRANT read, write ON DIRECTORY data_pump_dir TO scott;
What the error message is telling you, is that the user SCOTT does not have the privileges to write to DATA_PUMP_DIR.
SCOTT
DATA_PUMP_DIR
As the DBA run
grant read, write on directory DATA_PUMP_DIR to scott;
Is D:\app\Administrator\admin\orcl\dpdump\ a directory on the server? It has to be accessible from the Oracle server software to be valid, as the export actually runs on the server and not the client.