Thank you for writing to Aspose Support team.
are you sure you answered to the right question?
I wanted to know if there is a way to detect that a MSG file was created via Outlook using the MapiMessage or MailMessage API (C#).
Outlook MSG files sometimes need special “treatment” when converting to PDF…
If you have any ideas or input regarding that question I am still happy to hear about them.
You can load MSG file created by Outlook using MapiMessage. However, there is no APIs to detect either is it created via Outlook or not.
Could you please share some more detail about this special “treatment” by Outlook MSG file? We will then answer your query according to your requirements. Thanks for your cooperation.