Problems getting bullet collisions working

I am making a simple Galaxians game (new to Unity). I have a player ship firing prefab bullets from a spawner and I am trying to get them to collide with the aliens that were dynamically created from prefabs.

I have tried a number of things like continuous detection on both objects and messing with triggers and kinematics. Zs are the same. Here is the code which creates a bullet:

Here are three screenshots of the firing code, the bullet info and the ship info.

https://drive.google.com/folderview?id=0B7hUXatI4pmDeXRlblNUQ2Z2NmM&usp=sharing

Any help would be massively appreciated.

Paul

The bullet should contain a component like sphere collider or box collider and the IsTrigger property should be checked.
69947-istrigger.jpg
Then you attach a script to the bullet in which you have a method called OnTriggerEnter.

For example, you have an Enemy script with a public float variable called health. When the bullet collides with the object than contains the Enemy script, you destroy the bullet and apply damage to the enemy.

 void OnTriggerEnter(Collider other) 
       {
            other.gameObject.GetComponent<Enemy>().health -= 5; // Applies damage to the hit object
            Destroy(gameObject); // Destroys the bullet
       }

Information about OnTriggerEnter.

Thank you very much for the answer. I tried it, but still got nothing. There is something else I am missing. It is driving me crazy!!

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