When I tried to join in a fire fight at the Cosmodrome - I got shot at by fellow players. I figured out that I was interfering with their mission or something and they wanted to let me know to get away. Do people sometimes shoot you to get your attention so you can become friends? It sounds stupid but I can accept it if true. I won't interfere in any more fights and go it alone until somebody wants to make up a fire team with me. I don't require being some leader in the hunt - I can have just as much fun in support. I did it that way in the only Fire Team allowed me in Old Russia at level 8 and done well twice. I killed Septis Prime (with help of course) and helped the second time around with plenty of support.