I'm running into the classic scenario where, when creating Word COM objects in .NET (via the Microsoft.Office.Interop.Word assembly), the WinWord process won't exit even though I'm properly closing and releasing the objects.

I've narrowed it down to the use of the Word.Documents.Add() method. I can work with Word in other ways without a problem (opening documents, modifying contents, etc) and WinWord.exe quits when I tell it to. It's once I use the Add() method that the process is left running.

Here is a simple example which reproduces the problem:

Dim oWord As New Word.Application()
oWord.Visible = False

Dim oDocuments As Word.Documents = oWord.Documents

Dim oDoc As Word.Document = oDocuments.Add(Template:=CObj(sTemplatePath), NewTemplate:=False, DocumentType:=Word.WdNewDocumentType.wdNewBlankDocument, Visible:=False)

' dispose objects
oDoc.Close()
While (Marshal.ReleaseComObject(oDoc) <> 0)
End While
oDoc = Nothing

oWord.Quit()
While (Marshal.ReleaseComObject(oWord) <> 0)
End While
oWord = Nothing

As you can see I'm creating and disposing the objects properly, even taking the extra step to loop Marsha.ReleaseComObject until it returns the proper code. Working with the Word objects is fine in other regards, it's just that pesky Documents.Add that is causing me grief. Is there another object that gets created in this process that I need to reference and dispose of? Is there another disposal step I need to follow? Something else? Your help is much appreciated :)