How to download attachment files from .msg files using ruby-msg gem. save method is not working. I am working on ruby script

require ‘mapi/msg’

public_folder = “public”

msg_file_folder = “msg_file”

attachment_folder = ‘Attachment_pdf’

msg_file_name = ‘testfile.msg’

public_path = File.expand_path(public_folder)

file_path = File.join(public_path, msg_file_folder, msg_file_name)

download_file_path = File.join(public_path, attachment_folder)

msg = Mapi::Msg.open(file_path)

a = msg.attachments.first.save(“/test.pdf”)

puts msg.subject