DirectX Error

I am making a game called Battle Tank and I referenced a DirectX reference just as the tutorial said but I'm getting an error saying:

1 Error, The type 'Microsoft.DirectX.Direct3D.Device' exists in both 'c:\WINDOWS\Microsoft.NET\DirectX for Managed Code\2.0.0.0_x86\Microsoft.DirectX.dll' and 'c:\WINDOWS\Microsoft.NET\DirectX for Managed Code\1.0.2902.0\Microsoft.DirectX.Direct3D.dll'

Here's my code to the game:

using System;

using System.Collections.Generic;

using System.ComponentModel;

using System.Data;

using System.Drawing;

using System.Text;

using System.Windows.Forms;

using Microsoft.Samples.DirectX.UtilityToolkit;

namespace BattleTank2005

public partial class GameEngine : Form {

protected override void OnPaint(PaintEventArgs e) {

deltaTime = FrameworkTimer.GetElapsedTime();

FrameworkTimer.Start();

device.Clear(ClearFlags.Target, Color.DarkBlue, 1.0f, 0);

this.Invalidate();

public GameEngine()

this.SetStyle(ControlStyles.AllPaintingInWmPaint | ControlStyles.Opaque, true);

// Get the ordinal for the default adapter

int adapterOrdinal = Manager.Adapters.Default.Adapter;

// Get our device capabilities so we can check them to set up the CreateFlags

// Check the capabilities of the graphcis card is capable of

// performing the vertex-processing operations

// The HardwareVertexProcessing choice is the best

if (caps.DeviceCaps.SupportsHardwareTransformAndLight)

else

// If the graphics card supports vertex processing check if the device can

// do rasterization, matrix transformations, and lighting and shading operations

// This combination provides the fastest game experience

if (caps.DeviceCaps.SupportsPureDevice && createFlags == CreateFlags.HardwareVertexProcessing)

// Set up the PresentParameters which determine how the device behaves

PresentParameters presentParams = new PresentParameters();

// Make sure we are in windowed mode when we are debugging

#if DEBUG

presentParams.Windowed = true;

// Now create the device

device = new Device(

this,

private double deltaTime;

private Microsoft.DirectX.Direct3D.Device device;