ORA-01031 Insufficient privilege while creating Oracle user

login as "SYS" user

SQL> create user test identified by test;
ORA-01031: insufficient privilege

If you have "Enabled" Oracle Database Vault in your Database this could cause a problem

Solution is Disable Oracle Database Vault

SQL>exec dbms_macadam.disable_dv;

Restart the Database

SQL>create user test identified by test;
User created

SQL>