OnMouseEnter OnMouseExit, and Event Triggers Not Working?

I've tried everything, read all docs, and questions/answers i could find, Tried using those methods, Still didnt work at all. I tried 'OnMouseEnter' and 'onMouseEnter' same thing for the OnMouseExit, Still doesnt work.

Edit: My objects have BoxColliders on them, along with rigidbody. I get no errors. Only problem is 'OnMouseEnter();'

Code[Unity 5] (C# Because I don't like using JS):

 using UnityEngine;
 using System.Collections;
 using UnityEngine.UI;
 public class PickupItem : MonoBehaviour {

 public Text text;
 public string itemname;
 public string hoverMessage;
 public string pickupMessage;
 public bool mouseHover;
 public int itemID;
 public Inventory inv;
 public GameDB invAdd;
 public bool[] items;
 public int itemAmount;
 public bool pickedupItem;
 private float texttime;
 public float textTime;

 void Start () {
     texttime = textTime;
     inv = GameObject.FindObjectOfType<Inventory> ();
     invAdd = GameObject.FindObjectOfType<GameDB> ();
     text = GameObject.Find ("ItemPickupText").GetComponent<Text>();
 }

 void Update () {
     if (pickedupItem) {
         text.text = "" + pickupMessage + " [" + itemname + " x" + itemAmount + "]";
         texttime -= Time.deltaTime;

         if (texttime <= 0) {
             texttime = textTime;
             text.text = "";
             pickedupItem = false;
         }
     }

     if (!mouseHover) {
         text.text = "";
     }

     if (mouseHover) {
         if (Input.GetMouseButton (0)) {
             this.gameObject.transform.position = Input.mousePosition;
         }
     }
 }

 //Backup if Event Trigger Doesnt work
 public void OnMouseEnter(){
     Hover (true);
 }
 public void OnMouseExit(){
     Hover (false);
 }

 public void Hover(bool h){
     mouseHover = h;

     if (mouseHover) {
         text.text = "" + hoverMessage + " [" + itemname + " x" + itemAmount + "]";
         if (Input.GetKeyDown (KeyCode.E)) {
             if (items [0] = true) {
                 invAdd.AddWaterBottle (itemAmount);
                 pickedupItem = true;
             }
             if (items [1] = true) {
                 invAdd.AddChocolateBar (itemAmount);
                 pickedupItem = true;
             }
             if (items [2] = true) {
                 invAdd.AddCannedBeans (itemAmount);
                 pickedupItem = true;
             }
             if (items [3] = true) {
                 invAdd.AddGauze (itemAmount);
                 pickedupItem = true;
             }
             if (items [4] = true) {
                 invAdd.AddAxe (itemAmount);
                 pickedupItem = true;
             }
         }
     }
 }
 }