Every time i join my server, as an client, i get banned:

I readed a lot of posts, but i dont know abaut what pb cfg or anythink like that there is, to control this pb. I tryed to do a command when a ban is inussed for my ip, the ban to be stoped, but ofcoure it did't work (i'm not good at that stuff) . I need help! Please help me... I have Windows XP 2000.... If you need addinal information please ask...