VSTO AddIn for Word Only
The parent property just reverts to Microsoft Word and never Outlook. I ended up importing User32.dll and getting the Windows name and then checking if it contained Microsoft Word.
The only problem I'm still running into is that if a user opens Outlook, creates a new message, and then opens Word, the WINWORD.exe process still has what I assumed is the default template. and so the new copy word won't show my plugin.
Word has several properties that will allow you to determine whether it is running as a mail editor or not.
App.MailEnvelope App.Envelope App.Email
All information related to return email. I believe that at least one of these will return ANYTHING if the word is NOT used as an email editor, but I no longer have access to that code, so I couldn't be sure without trying to execute it.
However, I know that even MS recommends against using Word as your email editor. in Office 2007 and 2010, I no longer believe that even an option.
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