How do I tell it to use default/no password? Thank you.

NCP>DEFINE REMOTE
REMOTE NODE NAME(1-6 CHARS):XX
REMOTE NODE NUMBER(2-240):43
FILENAME FOR SECONDARY LOADER(1-13 CHARS,OPTIONAL):
FILE USED FOR TERTIARY LOADER(1-13 CHARS,OPTIONAL):
DOWN-LINE LOAD FILE(1-13 CHARS,OPTIONAL):
BOOTSTRAP PASSWORD(EXACTLY 4 CHARS,OPTIONAL):
PASSWORD REMOTE SENDS DURING INIT SEQUENCE(1-8 CHARS):
%NCP-E-BADPARS, unrecognized parameter "_NA"
PASSWORD REMOTE SENDS DURING INIT SEQUENCE(1-8 CHARS):