Having wrong texture on my model?

I wanna change material of object programmatically, i am using this code, and have assigned both variables in inspector view but when i run the program it show just pink texture on my object. here is my code and screen shot. please help and thanks in advance.

 #pragma strict

  var yourMaterial : Material;
  var newMaterial : Material;

 function Start () {
     renderer.material = yourMaterial;
 }

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[2]: /storage/temp/30721-screen+shot+2014-08-11+at+12.42.38+pm.png

[3]: /storage/temp/30721-screen+shot+2014-08-11+at+12.42.38+pm.png