dba_users view

Hi
I am getting an error when I tried this---->
SQL> desc dba_users;
ERROR:
ORA-04043: object dba_users does not exist


SQL> select username from dba_users;
select username from dba_users
*
ERROR at line 1:
ORA-00942: table or view does not exist

It used to work fine before. Any help would be appreciated to resolve this.

Thanks in advance.

Maybe someone has come to their senses and taken away access ... DBA_USERS is a dangerous view to be giving permission on.

have you connected with SYS user ? or any other user who has DBA role ?

Thanks vnktummala.
I have connected as a sys as well as other user with DBA role.
Thanks in advance.