System.NullReferenceException in every Game() parametters XNA

I’ve been experiencing a really Strange problem since recently, Every parameters of XNA Framework Game class seems to not be initialized before my extending Game1 () class. The Content manager and the Window that should not be null, but like after I’ve tried to add a dll pipeline (that makes my content pipeline crash by the way) everything started to go wrong like this problem. I’ve had this after trying to import a.fnt (did not work) and a localized Spritefont.

I do not plan to change the game engine, but I’ll appreciate any help of any kind.

Thanks for your time

here is my Game1 class (a small part of it)

public class Game1 : Game {   public static GraphicsDeviceManager graphics;   public static SpriteBatch spriteBatch;   public static ContentManager ContentManager;   public static SceneManager SceneManager { get; private set; }            public Game1()   {     ContentManager = Content;      graphics = new GraphicsDeviceManager(this);     ContentManager.RootDirectory = "Content";       // TODO: Add your initialization logic here     /*     GraphicsAdapter.DefaultAdapter.CurrentDisplayMode.Height     GraphicsAdapter.DefaultAdapter.CurrentDisplayMode.Width     */     Window.IsBorderless = true;     graphics.PreferredBackBufferWidth = GraphicsAdapter.DefaultAdapter.CurrentDisplayMode.Width;     graphics.PreferredBackBufferHeight = GraphicsAdapter.DefaultAdapter.CurrentDisplayMode.Height;     IsMouseVisible = true;    }      (...) //The code continues } 

and here is the errors:

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the Null pointer error on the Window variable occures when i declare a new Content manager