As is the case with so many elements of Windows and MFC programming, once you know the trick, it's easy. And it's interesting to note that this, our very first Tip, has nothing to do with MFC!

Call FindWindow to get a handle to a window with the same title as your application. If it comes back NULL, there are no windows with the same title, so you're okay. But if it returns a valid handle, show the window and bring it to the top.

See KB article Q141752 for a different method.

HWND hwnd = ::FindWindow(NULL, "title of your app"); if (hwnd) { ::ShowWindow(hwnd, SW_SHOWDEFAULT); ::BringWindowToTop(hwnd); } return FALSE;

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