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POC++ CreateWindowEx returns NULL
 

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  1. POC++ CreateWindowEx returns NULL
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    <p>I'm trying to set up a simple window using C++, but my call to <code>CreateWindowEx</code> returns <code>NULL</code>. Most of the code I'm using comes from the <a href="http://msdn.microsoft.com/en-us/library/windows/desktop/ff381409%28v=vs.85%29.aspx" rel="nofollow">example</a> on the MSDN website. Nothing that I've tried has worked, and any help would be appreciated.</p> <p>Here is the code:</p> <pre><code>//Include the windows header #include &lt;Windows.h&gt; //Forward declaration of the WndProc function LRESULT CALLBACK WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam); //Main entry point int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PWSTR pCmdLine, int nCmdShow) { //Window class name const wchar_t windowName[] = L"Window Class"; //Set up window class WNDCLASS wnd; wnd.lpfnWndProc = WndProc; wnd.hInstance = hInstance; wnd.lpszClassName = windowName; //Register window class RegisterClass(&amp;wnd); //Create window //! This returns NULL HWND hWnd = CreateWindowEx( 0, windowName, L"Windows Programming", WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL ); //Simple check to see if window creation failed if(hWnd == NULL) { //Pause system("PAUSE"); return -1; } //Show the window ShowWindow(hWnd, nCmdShow); //Main message loop MSG msg; while(GetMessage(&amp;msg, NULL, 0, 0)) { TranslateMessage(&amp;msg); DispatchMessage(&amp;msg); } } //WndProc function LRESULT CALLBACK WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam) { switch(msg) { case WM_PAINT: { PAINTSTRUCT ps; HDC hDc = BeginPaint(hWnd, &amp;ps); FillRect(hDc, &amp;ps.rcPaint, (HBRUSH) (COLOR_WINDOW + 1)); EndPaint(hWnd, &amp;ps); return 0; } case WM_DESTROY: { PostQuitMessage(0); return 0; } } return DefWindowProc(hWnd, msg, wParam, lParam); } </code></pre>
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    1. USPavel Strakhov
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    1. COI see no `GetLastError` in your code, but yet you're here. I notice a couple aspects of filling out your `WNDCLASS` are missing, though.
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      1. USchris
    2. COUse `GetLastError` to get the error code, and post it.
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      1. USNawaz
    3. CODid RegisterClass succeed? What did it return.
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      1. USScott Langham
 

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