PowerPoint hanging on Application.Quit call - com

Question

Here's the code I'm running:
MsoTriState readOnly = MsoTriState.msoTrue;
MsoTriState untitled = MsoTriState.msoFalse;
MsoTriState withWindow = MsoTriState.msoFalse;
string filePath; //some file path to a pptx
ppt.Application app = null;
ppt.Presentations presentations = null;
ppt.Presentation presentation = null;
app = new ppt.Application();
presentations = app.Presentations;
presentation = presentations.Open(filePath, readOnly, untitled, withWindow);
System.Runtime.InteropServices.Marshal.ReleaseComObject(presentation);
presentation = null;
System.Runtime.InteropServices.Marshal.ReleaseComObject(presentations);
presentations = null;
app.Quit(); //HANGING HERE
System.Runtime.InteropServices.Marshal.ReleaseComObject(app);
app = null;
It's a very basic code that opens a PowerPoint application and then closes it. However, for some reason, it is hanging on the app.Quit() call. Also, I don't know why, but if I comment out the line where I ComRelease presentation, it doesn't hang. An alternative hack is to make app.Visible = msoTrue before calling app.Quit.
Does anyone know what is going on here? Am I messing up my ComRelease procedure?

Answer 1

I have a workout for you here.you can found out the running process and kill it through code.
Code:
Process[] pros = Process.GetProcesses();
for (int i = 0; i < pros.Count(); i++)
{
if (pros[i].ProcessName.ToLower().Contains("powerpnt"))
{
pros[i].Kill();
}
}