Naga Trinity Mouse Button 4 and 5 back and forward

Hi everybody, I've just bought a Naga Trinity Mouse because I was really annoyed about the third Logitech mouse which the mouse wheel button was fucked up again. Now I am searching for the mouse button 4 and 5 function which allows me to go back and for in my windows explorer or browser. With the normal settings it won't work and in the setting options i can't find the settings to switch it. Perhaps someone have any clue for me ?!? I am using the Version 7.3.22.122 of Razer Central. Thanks in advance for your help ! Greetings Dekk