Не открывается GUI WinApi

#include <Windows.h>

LRESULT CALLBACK SoftwareMainProcedure(HWND hWnd, UINT msg, WPARAM wp, LPARAM lp);
WNDCLASS NewWindowClass(HBRUSH BGColor, HCURSOR Cursor, HINSTANCE hInst, HICON Icon, LPCWSTR Name, WNDPROC Procedure);

int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, LPSTR args, int ncmdshow) {
    HWND hWnd;
    WNDCLASS SoftwareMainClass = NewWindowClass((HBRUSH)COLOR_WINDOW, LoadCursor(NULL, IDC_ARROW), hInst, LoadIcon(NULL, IDI_QUESTION), L"MainWndClass", SoftwareMainProcedure);
    if (!RegisterClassW(&SoftwareMainClass)) { return -1; }
    MSG SoftwareMainMessage = { 0 };
    hWnd = CreateWindow(L"MainWndClass", L"First c++ window", WS_OVERLAPPEDWINDOW | WS_VISIBLE, 100, 100, 500, 250, NULL, NULL, NULL, NULL);
    while (GetMessage(&SoftwareMainMessage, NULL, NULL, NULL)) {
        TranslateMessage(&SoftwareMainMessage);
        DispatchMessage(&SoftwareMainMessage);
    }
    return 0;
}

WNDCLASS NewWindowClass(HBRUSH BGColor, HCURSOR Cursor, HINSTANCE hInst, HICON Icon, LPCWSTR Name, WNDPROC Procedure) {
    WNDCLASS NWC = { 0 };
    NWC.hCursor = Cursor;
    NWC.hIcon = Icon;
    NWC.hInstance = hInst;
    NWC.lpszClassName = Name;
    NWC.hbrBackground = BGColor;
    NWC.lpfnWndProc = Procedure;
    return NWC;
}
LRESULT CALLBACK SoftwareMainProcedure(HWND hWnd, UINT msg, WPARAM wp, LPARAM lp) {
    switch (msg)
    {
    case WM_CREATE:
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    default: return DefWindowProc(hWnd, msg, wp, wp);
    }
}

Не открывается GUI окошко, а процесс программы висит в диспетчере задач.

• c++

Опечатка: должно быть

default: return DefWindowProc(hWnd, msg, wp, lp);

вместо

default: return DefWindowProc(hWnd, msg, wp, wp);

Плюс обработчик WM_CREATE должен возвращать 0