What is wrong with this code?

      
#pragma once

int InitClass(char WindowName[]);
LRESULT CALLBACK MsgHandler(HWND, UINT, WPARAM, LPARAM);

// Globals.....I know

RECT WindowRect = {100, 100, 400, 400};
HINSTANCE hInstance; 
int iCmdShow;

InitClass(char WindowName[])
{
	MSG msg;
	HWND hwnd;
	WNDCLASSEX wndclass;

	// Class Properties

	wndclass.cbSize			   = sizeof(wndclass);
	wndclass.hInstance         = hInstance;
	wndclass.lpfnWndProc       = MsgHandler;
	wndclass.lpszClassName     = "Reusable Window";
	wndclass.style             = CS_HREDRAW | CS_VREDRAW;
	
	// Visual properties

	wndclass.hbrBackground     = (HBRUSH) GetStockObject(WHITE_BRUSH);
	wndclass.hCursor           = LoadCursor(NULL, IDC_ARROW);
	wndclass.hIcon             = LoadIcon(NULL, IDI_APPLICATION);
	wndclass.hIconSm           = LoadIcon(NULL, IDI_APPLICATION);
	
	RegisterClassEx(&wndclass);

	hwnd=CreateWindow("Reusable Window", WindowName, WS_OVERLAPPEDWINDOW || WS_VISIBLE,
					   WindowRect.left, WindowRect.top, WindowRect.right, WindowRect.bottom,
					   NULL, NULL, hInstance, NULL);
	
	ShowWindow(hwnd, iCmdShow);
	UpdateWindow(hwnd);

	while(GetMessage(&msg, NULL, 0, 0))
	{
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}

	return msg.wParam;
}

LRESULT CALLBACK MsgHandler(HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam)
{
	static TEXTMETRIC TextInfo;
	static int Length;
	PAINTSTRUCT PaintStruct;
	HDC hdc=NULL;
	int x, y;
	char Message[]="cmoWindow Test";

	switch(iMsg)
	{
	case WM_CREATE:
		hdc=GetWindowDC(hwnd);
		GetTextMetrics(hdc, &TextInfo);
		Length=strlen(Message);
		ReleaseDC(hwnd, hdc);
		break;
	case WM_SIZE:
		GetWindowRect(hwnd, &WindowRect);
		break;
	case WM_PAINT:
		hdc=BeginPaint(hwnd, &PaintStruct);
		SetTextColor(hdc, RGB(0, 0, 255));

		x=(WindowRect.right-WindowRect.left)/2;
		x=x-(Length*TextInfo.tmAveCharWidth)/2;

		y=(WindowRect.bottom-WindowRect.top)/2;
		y=y-(TextInfo.tmHeight)/2;
		TextOut(hdc, x, y, Message, Length);
		EndPaint(hwnd, &PaintStruct);
		break;
	case WM_DESTROY:
		PostQuitMessage(NULL);
		break;
	}
	
	return DefWindowProc (hwnd, iMsg, wParam, lParam);
}
  

        
#include <windows.h>

#include "cmoWindow.h"

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, 
					PSTR szCmdLine, int iCmdShow)	
    {
		
		InitClass("Hello World");
		return 0;
	}