Simple Directx8 Window...

I can't get this to work for the life of me been days now how sad I think it has something to do with creating the device or clearing the screen but I can't seem to find it. Any help or tips would be really nice still a noob

//------------------------------------------------------------------------------------

//	Name: Application Shell

//	Desc: A simple window shell that will be used later as a base of my games.

//------------------------------------------------------------------------------------

#include <Windows.h>
#include <d3dx8.h>
#include <d3d8.h>

#pragma comment(lib,"d3d8.lib")
#pragma comment(lib,"d3dx8.lib")


LPDIRECT3D8			g_D3D;	//Global IDirect3D8 object

LPDIRECT3DDEVICE8	g_pD3DDevice;
HWND				hWnd;

//------------------------------------------------------------------------------------

//	FUNCTION PROTOTYPES

//------------------------------------------------------------------------------------

int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPSTR lpCmdLine, int nCmdShow);
LRESULT CALLBACK WinProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam);
void D3D_Init(void);
void D3D_Render(void);
void D3D_Release(void);

//------------------------------------------------------------------------------------

//	Name: WinMain()

//	Desc: Main Entry Point

//------------------------------------------------------------------------------------

int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPSTR lpCmdLine, int nCmdshow)
{
	
	HWND			hWnd;
	MSG				msg;

	WNDCLASSEX		wc = { sizeof(WNDCLASSEX), CS_CLASSDC, WinProc, 0L, 0L, hInst,
						   NULL, NULL, NULL, NULL, "GameClass", NULL};

	//Register the class and exit on an error

	if(!RegisterClassEx(&wc))
		return MessageBox(NULL,"Error Registering Window Class.","Error", MB_OK
		
		);

	//Create the window 

	hWnd = CreateWindow("GameClass", "My Game Title", WS_OVERLAPPED, GetSystemMetrics(SM_CXSCREEN), 
						GetSystemMetrics(SM_CYSCREEN),400, 400, NULL, NULL, hInst, NULL);

	//Return on error creating the window.

	if(hWnd == NULL)
		return MessageBox(NULL, "Error Creating Window", "Error", MB_OK);

	//Show Window

	ShowWindow(hWnd, SW_SHOWNORMAL);
	UpdateWindow(hWnd);
	
	D3D_Init();
	//Clear out the message structure

	ZeroMemory(&msg, sizeof(msg));

	//Loop endlessly until you receive a quit message

	while(msg.message != WM_QUIT)
	{
		//Peek into queue and see if there is a message waiting

		if(PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
		{
			//There is a message! Handle it normally.

			TranslateMessage(&msg);
			DispatchMessage(&msg);
		}else{
			D3D_Render();
			//No messages waiting. Go ahead and do time-crucial stuff here, such as rendering graphics.

		}
	}

	//Unregister class

	UnregisterClass("GameClass", hInst);

	D3D_Release();
	//Exit application

	return 0;
}

//------------------------------------------------------------------------------------

//	Name: WinProc

//	Desc: Message procedure

//------------------------------------------------------------------------------------

LRESULT CALLBACK WinProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
	switch(msg)
	{
	case WM_DESTROY:
		PostQuitMessage(0);	//Tell windows to clase application.

		break;

		//Handle every other message.

	default: return DefWindowProc(hWnd, msg, wParam, lParam);
	}
	return 0;
}

//------------------------------------------------------------------------------------

//	Name: D3D_Init()

//	Desc: Initializes direct3d

//------------------------------------------------------------------------------------

void D3D_Init()
{
	if((g_D3D = Direct3DCreate8(D3D_SDK_VERSION)) == NULL) 
	{
		//Error

	}

	D3DDISPLAYMODE		d3ddm;
	d3ddm.Width			= 800;
	d3ddm.Height		= 640;
	d3ddm.RefreshRate	= 0;
	d3ddm.Format		= D3DFMT_R8G8B8;
	

	if(FAILED(g_D3D->GetAdapterDisplayMode(D3DADAPTER_DEFAULT, &d3ddm)))
	{
		//Error

	}

	D3DPRESENT_PARAMETERS d3dpp;

	//Clear out the structure

	ZeroMemory(&d3dpp, sizeof(d3dpp));

	//Full Screen

	d3dpp.Windowed							= FALSE;
	d3dpp.SwapEffect						= D3DSWAPEFFECT_FLIP;
	d3dpp.FullScreen_RefreshRateInHz		= D3DPRESENT_RATE_DEFAULT;
	d3dpp.FullScreen_PresentationInterval	= D3DPRESENT_INTERVAL_DEFAULT;
	d3dpp.BackBufferFormat                  = d3ddm.Format;

	if(FAILED(g_D3D->CreateDevice(D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hWnd,
					  D3DCREATE_SOFTWARE_VERTEXPROCESSING, &d3dpp, &g_pD3DDevice))) 
	{
	
		MessageBox(NULL, "Error Creating Device","Error",NULL);
		//Error

	}
}

//------------------------------------------------------------------------------------

//	Name: D3D_Render()

//------------------------------------------------------------------------------------

void D3D_Render()
{
	if(FAILED(g_pD3DDevice->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_RGBA(0,0, 200, 255),
								  1.0f, 0)))
	{
		MessageBox(NULL, "Error Clearing Backbuffer", "Error", NULL);
	}

	if(SUCCEEDED(g_pD3DDevice->BeginScene()))
	{
		//Put fun stuff here


		g_pD3DDevice->EndScene();
	}
	
	g_pD3DDevice->Present(NULL, NULL, NULL, NULL);
}
//------------------------------------------------------------------------------------

//	Name: D3D_Release()

//	Desc: Release

//------------------------------------------------------------------------------------

void D3D_Release()
{
	if(g_pD3DDevice)
	{
      g_pD3DDevice->Release();
      g_pD3DDevice=NULL;
	}

   if(g_D3D)
   {
      g_D3D->Release();
      g_D3D=NULL;
   }
}

Thanks in advance Sorry normally just read the posts not post OK, when I run the program I get this error Unhandled exception at 0x004121f7 in Application Shell.exe: 0xC0000005: Access violation reading location 0x00000000. After that nothing else happens, my message box comes up saying error creating device, but i can't find whats wrong. [edited by - Diamend on January 14, 2004 9:34:52 AM] [edited by - Diamend on January 14, 2004 9:37:58 AM]