What's the correct email attachment MIME type for a zipped and password protected file?

Question

It's zipped and password protected with 7zip, should the mimetype be "application/7zip", or just "data/binary"? Something else?

Answer 1

According to Wikipedia (7z article), the mime type of a 7zip archive is application/x-7z-compressed, having a password on it will not change the mimetype.

If it is a zip (ie. not 7-zip file), the mimetype should be application/zip