/// <summary>
        /// converte message to eml format
        /// </summary>
        /// <param name="email"></param>
        public static void ConverteToEml(ApiEmail email, List <Attachment> attac, string folderPath)
        {
            Mime       emlmes     = new Mime();
            MimeEntity mainEntity = emlmes.MainEntity;

            mainEntity.From = new AddressList();
            mainEntity.From.Add(new MailboxAddress(email.Sender.Name, email.Sender.EmailAddress));
            mainEntity.To = new AddressList();
            mainEntity.To.Add(new MailboxAddress(email.Recipient[0].Name, email.Recipient[0].EmailAddress));
            mainEntity.Subject                 = email.Subject;
            mainEntity.ContentType             = MediaType_enum.Multipart_mixed;
            mainEntity.ContentTransferEncoding = ContentTransferEncoding_enum.QuotedPrintable;

            MimeEntity textEntity = mainEntity.ChildEntities.Add();

            textEntity.ContentType             = MediaType_enum.Text_plain;
            textEntity.ContentTransferEncoding = ContentTransferEncoding_enum.QuotedPrintable;
            textEntity.DataText = email.Message;

            MimeEntity htmlEntity = mainEntity.ChildEntities.Add();

            htmlEntity.ContentType             = MediaType_enum.Text_html;
            htmlEntity.ContentTransferEncoding = ContentTransferEncoding_enum.QuotedPrintable;
            htmlEntity.DataText = email.Html;

            mainEntity.Date        = email.Date.Value;
            mainEntity.MessageID   = GetEmailMetadata(email.message, "Message-ID");
            mainEntity.MimeVersion = GetEmailMetadata(email.message, "MIME-Version");
            if (attac.Count != 0)
            {
                foreach (var att in attac)
                {
                    MimeEntity attachmentEntity = mainEntity.ChildEntities.Add();
                    attachmentEntity.ContentTypeString       = att.mimeType;
                    attachmentEntity.ContentDisposition      = ContentDisposition_enum.Attachment;
                    attachmentEntity.ContentTransferEncoding = ContentTransferEncoding_enum.QuotedPrintable;
                    attachmentEntity.Data = att.name;
                    attachmentEntity.ContentDisposition_FileName = att.namestr;
                }
            }
            emlmes.ToFile(folderPath + "\\" + email.message.Id + ".eml");
        }