Main Menu Text Rendering error

I am trying to change the color of the text
This is The Script

function OnMouseEnter ()
{
GUIText.Renderer.Material.Color = Color.red;
}

function OnMouseExit ()
{
GUIText.Renderer.Material.Color = Color.white;
}

I Keep getting this error
NullReferenceException: Object reference not set to an instance of an object
Boo.Lang.Runtime.RuntimeServices.GetDispatcher (System.Object target, System.String cacheKeyName, System.Type[ ] cacheKeyTypes, Boo.Lang.Runtime.DynamicDispatching.DispatcherFactory factory)
Boo.Lang.Runtime.RuntimeServices.GetDispatcher (System.Object target, System.Object[ ] args, System.String cacheKeyName, Boo.Lang.Runtime.DynamicDispatching.DispatcherFactory factory)
Boo.Lang.Runtime.RuntimeServices.GetProperty (System.Object target, System.String name)
UnityScript.Lang.UnityRuntimeServices.GetProperty (System.Object target, System.String name)
RenderingScript.OnMouseExit () (at Assets/Main Menu/Scripts/RenderingScript.js:9)
UnityEngine.SendMouseEvents:smile:oSendMouseEvents(Int32, Int32)

Please Help Me

Pay attention to your capitalization; none of the items in “GUIText.Renderer.Material.Color” should be capitalized. You should be referring to the variables, not the classes.

–Eric