FindGameObjectsWithTag not finding tagged objects

I’m attempting to follow some of the BergZerg tutorials and I’m on the targeting section right now. Unfortunately I cannot seem to get my script to add any tagged objects. All my enemy objects are tagged with the tag Enemy and I am using the code below. I have even tried to change the tag to Player and it did not pick the player. I created a new tag “enemy” with the lower case “e” and it still did not pick it up. I’m at a loss.

using UnityEngine;
using System.Collections;
using System.Collections.Generic;

public class Targeting : MonoBehaviour {
	
	public List<Transform> targets;
	
	// Use this for initialization
	void Start () {
		targets = new List<Transform>();
	}
	//Add enemies to array
	public void AddAllEnemies(){
		GameObject[] go = GameObject.FindGameObjectsWithTag("Enemy");
		
		foreach(GameObject enemy in go)
			AddTarget(enemy.transform );
	}
	// Add enemies to player target
	public void AddTarget(Transform enemy){
		targets.Add(enemy);
	}
	
	// Update is called once per frame
	void Update () {
	
	}
}

Where are you calling your function AddAllEnemys from? If not at all, add the call to the start function…I dont read C# very well, but i think this is the main prob here.