ArgumentOutOfRangeException: Argument is out of range? What wrong?

Well I've tried every thing I know (which isn't much considering I'm a noobie) to fix this. Can some one help me fix the Error. Here is my code ItemClass:

 public class ItemClass
 {
 public var name : String;
 public var description : String;
 public var icon : Texture2D;
 public var itemType : ItemType;
 enum ItemType{None, Weapon, Other}
 
 }`

Inventory Script

 import System.Collections.Generic;
 
 var playerInventory : List. = new List.();
 var scrollView : Vector2;
 var Weapon : ItemClass;
 var equipped : boolean = false;
 
 function Update () {
 
 }
 
 function OnGUI () 
 {
 
     GUILayout.BeginArea(Rect(Screen.width - 100,0,100,100));
 
     scrollView = GUILayout.BeginScrollView(scrollView, GUILayout.Width(100), GUILayout.Height(100));
     for(var x = 0; x < playerInventory.Count; x++)
     {
 
     GUILayout.BeginHorizontal();
         if(GUILayout.Button(playerInventory[x].icon))
         {
             playerInventory.RemoveAt(x);
             return;
         }
         GUILayout.Box(playerInventory[x].name);
         GUILayout.EndHorizontal();
         GUILayout.Box(playerInventory[x].description);
     }
     GUILayout.EndScrollView();
     GUILayout.EndArea();
 
     if(GUI.Button(Rect(Screen.width/2 - 25, Screen.height - 50,50,50), Weapon.icon)){
 
 
         }
     
     }`

AddItem Script:

 import System.Collections.Generic;
 
 var loot : ItemClass[];
 var Inventory : Inventory;
 
 function Start () {
 Inventory = GetComponent("Inventory") as Inventory;
 }
 
 function OnGUI () {
 
 GUILayout.BeginArea(Rect(0,0,60,60));
 if(GUILayout.Button("loot"))
     {
         giveloot();
     }
 GUILayout.EndArea();
 
 }
 
 function giveloot() {
 
 for(var x = 0; x < loot.length; x++)
 Inventory.playerInventory.Add(loot[x]);
 }

These are the three scripts I am using to make an Inventory. Any help would be appreciated. Thanks in Advanced.