EDIT: I am not asking HOW to save email from Outlook in EML format. Hence this question is not a duplicate of How to save a mail into an .eml-file with Outlook? !
I cannot find any relevant reference to the missing full support for the EML format in Microsoft Outlook, i.e. including export. (And yes, I do know that you can open an EML file in Outlook :) )
Is it a deliberate Microsoft decision, why you cannot save emails in the EML format? Or is it only "low priority"? Is it a remnant of the many Microsoft vendor lock-in attempts from the past? Has Microsoft ever made any statement about this missing interoperability function?
