Animation Loop Disable? (WrapMode)

Okay so, I imported this model to Unity. It's include with walk animations. So set the animation to "Legacy" and imported it to models. It works

Then, I want to make animations to loop. But WrapMode seems disabled! And when I try to open the animations, it's unable to open! And it gives me an error! The model is .fbx type

Please help me

[SOLVED] I just put this script to my model

 function Start ()
 {
     this.animation.wrapMode = WrapMode.Loop;
 }

I don't that this will still work if I add more script that include animations