Collision not working

I have a empty game object named house. Inside which I have 3 cubes, one named ‘Trig’ and the other 2 just ‘cube’. I also have box colliders on all of them. I want it to load the next level when the player collides in the ‘Trig’ cube. But my game won’t. Here is my script:

#pragma strict

function OnCollisionEnter (col : Collision) {

	if( == "Trig") {


It also shows an error in the console : NullReferenceException: Object reference not set to an instance of an object
MeshFilterEditor.OnEnable ()

MeshFilterEditor is not assign. Check this 1st.

Try to add Rigibody component.
Disable isTrigger flag that for onTrigger() only.
Maybe OnTrigger() is more suitable for you.