You can see this type of ora error when executing a command like:

ALTER TABLE CUSTOMER_SERVICE
DEFAULT DIRECTORY 'IMP_DIR';

ORA-22929: invalid or missing directory name

The problem is in the single quotes surrounding the directory object name.
The same error is also returned when using a CREATE TABLE statement.

The correct syntax requires either double quotes for case sensitive names or no quotes at all for case insensitive names.

ALTER TABLE IMP_BAD_BOXES
DEFAULT DIRECTORY "IMP_DIR";

or

ALTER TABLE IMP_BAD_BOXES
DEFAULT DIRECTORY IMP_DIR;

Note that when using case sensitive names, if you mistype the name you'll get:

ORA-06564: object Import_Dir does not exist

ERROR at line 7:
ORA-22929: invalid or missing directory name
Can anyone clarify this..

CREATE TABLE SAMPLE2_EXT (
field1 varchar2(4000)
)
ORGANIZATION EXTERNAL
(
TYPE ORACLE_LOADER
DEFAULT DIRECTORY /u02/oradata/imp/
ACCESS PARAMETERS
(
records delimited by newline
badfile DAT_DIR:'SAMPLE2_EXT%a_%p.bad'
logfile DAT_DIR:'SAMPLE2_EXT%a_%p.log'
fields LRTRIM REJECT ROWS WITH ALL NULL FIELDS (field1 char(4000))
)
LOCATION ('sample2.dat')
)
REJECT LIMIT 10;

You need to specify the name of the directory not the actual location.

DEFAULT DIRECTORY /u02/oradata/imp/

#/u01/oracle>sqlplus system/pwdcreate or replace directory ext_dir as '/tmp';   --> EXT_DIR is a directory name

grant read, write on directory ext_dir to james;

connect james/james@ora10g

CREATE TABLE ext_table_csv 

(  sifra_kpc    VARCHAR2(10),   

brojilo      VARCHAR2(20))

ORGANIZATION EXTERNAL( TYPE oracle_loader  

DEFAULT DIRECTORY ext_dir                        --> EXT_DIR is then used in CREATE TABLE statement...

Cause: The required directory name is invalid or missing.

Action: Specify a valid name.

Please add more information about this Error