Идентификатор не определен

#include "lb.h"
 
WNDCLASS            wc;
MSG                 msg;
HWND                hWnd;
HINSTANCE           hInst;
 
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
 
int APIENTRY _tWinMain(HINSTANCE hInstance,
    HINSTANCE hPrevInstance,
    LPTSTR IpCmdLine, int nCmdShow)
 
{
    UNREFERENCED_PARAMETER(hPrevInstance);
    UNREFERENCED_PARAMETER(lpCmdLine);
 
    hInst = hInstance;
    wc.style = CS_HREDRAW | CS_VREDRAW;
    wc.lpfnWndProc = WndProc;
    wc.cbClsExtra = 0;
    wc.cbWndExtra = 0;
    wc.hInstance = hInstance;
    wc.hIcon = LoadIcon(hInstance, NULL);
    wc.hCursor = LoadCursor(NULL, IDC_ARROW);
    wc.hbrBackground = (HBRUSH)(COLOR_WINDOW + 1);
    wc.lpszMenuName = NULL;
    wc.lpszClassName = _T("IbWinApi");
 
    RegisterClass(&wc);
 
    hWnd = CreateWindow(_T("lbWinApi"), _T("Каркас приложения"),
        WS_CAPTION | WS_SYSMENU, CW_USEDEFAULT, CW_USEDEFAULT,
        400, 250, NULL, NULL, hInstance, NULL);
 
    if (!hWnd) return FALSE;
 
    ShowWindow(hWnd, SW_SHOW);
 
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
 
    return (int)msg.wParam;
}
 
LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    PAINTSTRUCT ps;
    HDC hdc;
    RECT rect;
    TCHAR text[] = _T("Каркас приложения на WinApi");
 
    switch (message)
    {
    case WM_PAINT:
        hdc = BeginPaint(hWnd, &ps);
        GetClientRect(hWnd, &rect);
        DrawText(hdc, text, -1, &rect, DT_SINGLELINE | DT_CENTER | DT_VCENTER);
        EndPaint(hWnd, &ps);
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    default:
        return DefWindowProc(hWnd, message, wParam, lParam);
    }
    return 0;
}