Strange fullscreen/windowed problem

I'm working on a 3D engine that uses D3D 9 (unmanaged). After lots of confusion I finally came up with some code that will switch between fullscreen and windowed mode. Here is most of it: // Determine the new window style DWORD dwstyle = (FullScreen)?dwstyleFull:dwstyleWin; // Apply the new window style ShowWindow(hWnd, SW_HIDE); SetWindowLong(hWnd, GWL_style, dwstyle); SetWindowPos(hWnd, HWND_TOP, 0, 0, 0, 0, SWP_NOMOVE|SWP_NOSIZE|SWP_NOZORDER|SWP_FRAMECHANGED); ShowWindow(hWnd, SW_SHOW); // Calculate the new size of the window based on the client size RECT clientArea = {0, 0, D3DPP.BackBufferWidth, D3DPP.BackBufferHeight}; AdjustWindowRect(&clientArea, dwstyle, false); // Apply the new window position MoveWindow(hWnd, 0, 0, clientArea.right-clientArea.left, clientArea.bottom-clientArea.top, true); // Apply the new fullscreen mode and size to the backbuffer D3DPP.Windowed = !FullScreen; D3DPP.FullScreen_RefreshRateInHz = (D3DPP.Windowed)?0:iRefreshRate; D3DPP.BackBufferFormat = (D3DPP.Windowed)?(D3DFMT_UNKNOWN):(D3DFMT_X8R8G8B8); // Reset the device Reset(); The code makes a few calls to internal engine functions, but it should be clear what's going on. The problem is that after I switch from fullscreen mode to windowed mode, the window always stays on top! I can bring other windows into focus, but for some reason they remain behind the D3D window. I'm not sure if the problem lies within the code above but any help would be greatly appreciated. Also, if there is a better way to switch between fullscreen/window, please do tell. (Should I use 2 separate windows, and hide the inactive one?) I haven't seen any documentation on this.