Cause: A role granted was IDENTIFIED
EXTERNALLY. External roles cannot be granted to global users or global
roles.
Action: Use ALTER ROLE to change the
type of the role being granted (from IDENTIFIED EXTERNALLY to other, such as
IDENTIFIED BY password), or use ALTER ROLE or ALTER USER to change the type of
the user or role that is the grantee.

Relared Errors:
ORA-28023: must
revoke grants of this role to other user(s) first
ORA-28024: must
revoke grants of external roles to this role/user
ORA-28025:
missing or null external name
ORA-28026: user
with same external name already exists
ORA-28027:
privileged database links may be used by global users
ORA-28028:
could not authenticate remote server
ORA-28029:
could not authorize remote server for user string
ORA-28030:
Server encountered problems accessing LDAP directory service
ORA-28031:
maximum of string enabled roles exceeded
ORA-28035:
Cannot Get Session Key for Authentication