Oracle Expdp

 I was trying export a schema in Oracle 11G with a user name "MYUSER", but i get this error:

ORA-39002: invalid operation
ORA-39070: Unable to open the log file.
ORA-39145: directory object parameter must be specified and non-null   

I had already set up DATA_PUMP_DIR, you can check the location with this command:

SELECT owner, directory_name, directory_path  FROM all_directories

This error is because "MYUSER" doesn't have permission, you can allow "MYUSER" use expdp executing this command:

 grant exp_full_database to MYUSER;