Generate file to Create new email for Outlook, with Bcc field properly set and ready for UTF-8

I need to programatically open outlook 2016 on users computer, with new message, which contains the predefined fields (To, Bcc, UTF-8 body, attachment). For that, I need to generate either a file which outlook opens as a new message, or a script which makes outlook open the new message. It may look like an easy task, but it is actually tricky. I would, for example, do it in a way that I generate an .eml file, with content like this: ------ start cut ---- From: info @ [login to view URL] To: to @ [login to view URL] Cc: cc @ [login to view URL] Bcc: bcc @ [login to view URL] X-Unsent: 1 Subject: Something This is a test message. Multipart can be used to add attachment. ------ end cut ---- The problem is that this won't work, because if such file is opened by outlook (as .eml file), outlook is able to open it, but it ignores Bcc line entirely. So in another iteration, I would try to make a VBS script instead: ----------- start cut ------------ Set objoutlookApp = CreateObject("[login to view URL]") Set objmessage = [login to view URL](olMailItem) [login to view URL] = "mail1 @ [login to view URL];mail2 @ [login to view URL]" [login to view URL] = "cc1 @ [login to view URL];cc2 @ [login to view URL]" [login to view URL] = "bcc @ [login to view URL]" [login to view URL] = "E-Mail Subject" [login to view URL] = "Here comes some text" [login to view URL] set objmessage = Nothing set objoutlookApp = Nothing [login to view URL] --------- end cut ----------- This seems a bit better, but is still insufficient. First of all, the VBS file cannot be in UTF-8 format, thus it's not possible to send an email in chinese, for example, I need to be able to write UTF-8 encoded string directly to the body since it needs to be a single-file solution. And second, I have no idea how to add atachments (multipart) this way. So, your goal in this project is to develop a solution how to either format the .eml file or write a VBS script in a way which works for outlook 2016, and supports UTF-8 and optionally custom headers for multipart definition for attachments. You will provide a single file, which, after it's opened on users computer (windows with outlook) it opens a New Mail dialog with predefined to,cc,bcc,body fields with UTF-8 body.