Object reference not set to an instance of an object.

Hello everyone. I started using Unity today and I made a character that can shoot. Now I want my "Bullets" to disappear with an explosion when coliding with something. The explosion occurs, however the bullet does not disappear. This is my Destroy object code:

 var explosion : GameObject;
 
 function Update(){
 
 }
 function OnCollisionEnter(collision : Collision){
 var explosionClone=Instantiate(explosion, transform.position,transform.rotation);
 explosionClone.GetComponent("D­etonator").Explode();
 Destroy(gameObject);
 }

Does anyone know what's causing the problem? Any help is highly appreciated. Cheers, Andrew.

• Problem Fixed. Restarting Unity fixes it.