trouble with triggers

Unity Engine
1

I’m trying to get a model to stop walking, when it enters a Collider trigger, then play the attack animation…I have this script and a circle Collider on the model set to IsTrigger…when it hits the player its supposed to stop, but doesn’t…The Player is tagged with player…the animation state is set to a bool,when the walking animation is played the bool is false, when the trigger is touched, the bool is true, then the attack is played.
What am I doing wrong?..The model walks right into the player and the trigger isn’t working, until I back off the player a little, then it plays…the trigger just isn’t triggering like its suppose to. this is all happening on a NavMesh and I’m using Unity 4.6
.

using UnityEngine;
using System.Collections;
 
public class zombieIdleTrigger : MonoBehaviour
{
 
    Animator anim;
    NavMeshAgent agent;
    Transform Player;
 
    void Awake()
    {
        anim = GetComponent<Animator>();
        agent = GetComponent<NavMeshAgent>();
        Player = GameObject.FindGameObjectWithTag("Player").transform;
        anim.SetBool("zombieStop",false);
    }
   
    void OnTriggerEnter (Collider other)
    {
        if(other.gameObject.tag =="Player")
        {
            anim.SetBool("zombieStop",true);
            agent.speed = 0;
            Debug.Log("ENTERED");
        }
    }
 
 
 
    void OnTriggerExit (Collider other)
    {
        if(other.gameObject.tag =="Player")
        {
            anim.SetBool("zombieStop",false);
            agent.speed = 3;
            Debug.Log("EXIT");
        }
    }
}
2 
using UnityEngine;
using System.Collections;
 
public class zombieIdleTrigger : MonoBehaviour
{
 
    Animator anim;
    NavMeshAgent agent;
    Transform Player;
    public navmeshImproved navScript;
    public int ZombieSpeed = 0;
 
    void Awake()
    {
        anim = GetComponent<Animator>();
        agent = GetComponent<NavMeshAgent>();
        Player = GameObject.FindGameObjectWithTag("Player").transform;
        anim.SetBool("zombieStop",false);
    }
   
    void OnTriggerEnter (Collider other)
    {
        if(other.gameObject.tag =="Player")
        {
            anim.SetBool("zombieStop",true);
            navScript.enabled = false;
            agent.enabled = false;
            agent.speed = 0;
            Debug.Log("ENTERED");
        }
    }
 
 
 
    void OnTriggerExit (Collider other)
    {
        if(other.gameObject.tag =="Player")
        {
            anim.SetBool("zombieStop",false);
            navScript.enabled = true;
            agent.enabled = true;
            agent.speed = ZombieSpeed;
            Debug.Log("EXIT");
        }
    }
}

nevermind…needed more stuff in script