How to make the powerpoint.slideshowwindow.run() method without showing any visible windows?

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C#

PowerPoint

I am using DXGI to capture the PPT screen and start PPT in the background by calling Microsoft.Office.Interop.PowerPoint. However, after PowerPoint.SlideShowSettings.Run() is executed, the PPT window will popup. I found it can be hidden again later, but how to make the opening process completely invisible to users.

What I have tried:

PowerPoint.Application pptApp = new PowerPoint.Application();
//pptApp.Visible = Office.MsoTriState.msoTrue;
//pptApp.ShowWindowsInTaskbar = Office.MsoTriState.msoFalse;
//pptApp.Left = 0;

PowerPoint.Presentation oPre = pptApp.Presentations.Open("D:\\Document\\1.pptx", Office.MsoTriState.msoTrue, Office.MsoTriState.msoFalse, Office.MsoTriState.msoFalse);

PowerPoint.SlideShowSettings oSlideShowSettings = oPre.SlideShowSettings;
oSlideShowSettings.LoopUntilStopped = Office.MsoTriState.msoFalse;
oSlideShowSettings.ShowType = PowerPoint.PpSlideShowType.ppShowTypeWindow;
oSlideShowSettings.ShowWithNarration = Office.MsoTriState.msoFalse;
oSlideShowSettings.ShowWithAnimation = Office.MsoTriState.msoTrue;
oSlideShowSettings.AdvanceMode = PowerPoint.PpSlideShowAdvanceMode.ppSlideShowManualAdvance;
oSlideShowSettings.ShowScrollbar = Office.MsoTriState.msoFalse;

PowerPoint.SlideShowWindow oSlideShowWindow = oSlideShowSettings.Run();

int pptHwnd = pptApp.HWND;
IntPtr hPPTWnd = new IntPtr(pptHwnd);
ShowWindow(hPPTWnd, SW_HIDE);