Hi,
We did when after the get transaction (get single email), after get the single email, then check all attachment name, for some reasons, the .msg attachment file doesn’t has extension (e.g. email_title rather than email_title.msg).
Once found the file with no extension in the for each loop, just update the media type to “message/rfc822”, below is the example. AttachmentCount was used to help identify the attachment that need to update media type.
MailMessage(0).Attachments(AttachmetnCount).ContentType.MediaType = “message/rfc822”