Error Trying to Download a Image from a Local File

Hi Guys I Need your help. Im Download a image from a Local File, and before the build the test looks perfect, but when i build it it didnt work, i put the build debug and throw me this: "You are trying to load data from a www stream which has the following error when downloading Couldn't open the file"

Anyone know why? Why it works before build and it wont work after build?

Thanks a lot guys.

  public GameObject quad;
         Texture2D tex;

 The Other Method: 
 
 IEnumerator LoadContent(string path){
         WWW www = new WWW("file:///"+path);
         tex = new Texture2D(64,64);
         yield return www;
         www.LoadImageIntoTexture(tex);
         quad.renderer.material.mainTexture = tex;
         Image img = quad.GetComponent<Image> ();
         img.texture = tex;
     }