My company has custom code on our Infopath forms for printing, saving, and submitting via email. After upgrading to Office 2016 the Submit function no longer works. When the "Submit" button is pressed an error appears that says "To use this feature, Microsoft Outlook 2010 must be set as the default email program." We no longer have Outlook 2010 so that cannot be set as the default mail program. I'm not a programmer but I assume something could be put in the code so it uses whichever version of Outlook is installed? Would anyone have any idea what that would be? Here is the line in the code we are currently using that does not work: var mail = XDocument.View.Window.MailEnvelope