on *:TEXT:!test*:*:{
set -u300 %!test $nick
DCC Chat $nick
}
on *:OPEN:=:{
if ($nick == %!test) {
unset %!test
msg =$nick This is a test.
}
}
on *:OPEN:=:{
if ($nick == %!test) {
if ( $1- == hello ) {
msg =$nick Hi
}
}
}

i want it so fi somebody say hello in the dcc window, i will reply with "hi"

on *:TEXT:!test*:*:{
set -u300 %!test $nick
DCC Chat $nick
}
on *:OPEN:=:{
if ($nick == %!test) {
.msg $nick This is a test.
}
}
on *:CHAT:hello:{
if ($nick == %!test) { .msg $nick Hi }
}

try that... i think it should work

just an idea, you have the variable set %!test, try just %test, the negate feature "!" usually has another reasoning, in mirc script, so try removing the ! and good luck

never really used the dcc chat for any reason but i think where you have $nick in the On Open and On Chat events it would need to be =$nick ?

yes as he had in his original code