Reply to Can't get the fighter working with ableton??

I've just got the midi fighter and I've just got the new version of ableton 9 but I can't seem to get it working with it? I just wanted to know if it was something simple I wasn't doing? In preferences the midi fighter is there in the midi tab but I switch it on but the green light doesn't come on to say that it's got a midi signal going to it.
Can anyone help please