Не создается окно функцией CreateWindow - C++ WinAPI - Ответ 9084745

#include "KWnd.h"
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
 
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
{
    MSG msg;
    KWnd mainWnd(TEXT("Application"), hInstance, nCmdShow, WndProc);
 
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
 
    return msg.wParam;
}

class KWnd
{
protected:
    HWND hWnd;
    WNDCLASSEX wc;
public:
    KWnd(LPCTSTR windowName, HINSTANCE hInst, int cmdShow, LRESULT(WINAPI *pWndProc)(HWND, UINT, WPARAM, LPARAM),
        LPCTSTR menuName = NULL, int x = CW_USEDEFAULT, int y = 0, int width = CW_USEDEFAULT, int height = 0,
        UINT classStyle = CS_HREDRAW | CS_VREDRAW, DWORD windowStyle = WS_OVERLAPPEDWINDOW, HWND hParent = NULL) 
    {
        PTSTR szClassName = TEXT("KWndClass");
 
        wc.cbSize = sizeof(wc);
        wc.style = classStyle;
        wc.lpfnWndProc = pWndProc;
        wc.cbClsExtra = 0;
        wc.cbWndExtra = 0;
        wc.hInstance = hInst;
        wc.hIcon = LoadIcon(NULL, IDI_APPLICATION);
        wc.hCursor = LoadCursor(NULL, IDC_ARROW);
        wc.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
        wc.lpszMenuName = menuName;
        wc.lpszClassName = szClassName;
        wc.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
 
        if (!RegisterClassEx(&wc))
        {
            TCHAR msg[50] = TEXT("Cannot register class: ");
            lstrcat(msg, szClassName);
            MessageBox(NULL, msg, TEXT("Error"), MB_OK);
            exit(0);
        }
 
        hWnd = CreateWindow(szClassName, windowName, windowStyle, x, y, width, height, hParent, (HMENU)NULL, hInst, NULL);
 
        if (!hWnd)
        {
            TCHAR msg[50] = TEXT("Cannot create window: ");
            lstrcat(msg, szClassName);
            MessageBox(NULL, msg, TEXT("Error"), MB_OK);
            exit(0);
        }
 
        ShowWindow(hWnd, cmdShow);
    }
 
    HWND GetHWnd() { return hWnd; }
};