Made a turret but can't get it to shoot !?

What am i doing wrong?

var LookAtTarget : Transform;
var damp = 6.0;
var bulletPrefab:Transform;

function Update ()
{
	if(LookAtTarget)
	{
		var rotate = Quaternion.LookRotation(LookAtTarget.position - transform.position);
	
		transform.rotation = Quaternion.Slerp(transform.rotation, rotate, Time.deltaTime * damp);
	
		shoot();
	}
}

function shoot()
{
	var bullet = Instantiate(bulletPrefab ,transform.Find("spawnPoint").transform.position ,
							Quaternion.identity);
							
	bullet.rigidbody.AddForce(transform.forward * 2000);
}

Try this …

function shoot() { 
            var bullet : GameObject = Instantiate(bulletPrefab ,GameObject.Find("spawnPoint").transform.position , transform.rotation) as GameObject; 
            bullet.rigidbody.AddForce(transform.forward * 2000);
}

Try this, put the var at the top of your script then drag the missile to launch into the RPG in the inspector …

var RPG : GameObject;

function shoot() { 
	var projectile : GameObject = Instantiate(RPG, GameObject.Find("spawnPoint").transform.position, transform.rotation) as GameObject;
		projectile.rigidbody.AddForce(transform.forward * 2000);
}