邮件发送没有到达收件人

Question

我已经使用cron作业调度程序通过在mail.properties中配置邮件设置用户名和密码向多个收件人发送自动邮件，同时向多个客户端发送邮件我注意到异常显示gsmtp异常，即使邮件限制未超过当天

@Scheduled(cron = "0 0 1 * * *")
    / * Weekly runs @ 01:00AM
     * Sends the DDR Pending count - email to Consortia Member and cc to CA[Configurable]
     */
    public void sendDDRPendingAutoMailToMember() {
        ArrayList<DDRAutoMailSchedulerVO> clientListForAutoMail = iDDRReportManager.getClientListForAutoMail();
        iMailManager.sendMailToCM(clientListForAutoMail);        
    }

@Override
    public void sendMailToCM(ArrayList<DDRAutoMailSchedulerVO> clientListForAutoMail) {
        SimpleDateFormat sdf = new SimpleDateFormat("dd-MM-yyyy");
        Calendar c = Calendar.getInstance();
    c.add(Calendar.DATE, -1);
    String temp_subject = " Pending DDR as of " + sdf.format(c.getTime());
        try {
            String jndiName = "java:comp/env/jdbc/JgateDatasource";    
            javax.sql.DataSource dataSrc;
            InitialContext icxt = new InitialContext();
            dataSrc = (javax.sql.DataSource)icxt.lookup(jndiName);
            Connection connection = dataSrc.getConnection();
            int mailSendCount = 0;
            for(DDRAutoMailSchedulerVO clientDetail : clientListForAutoMail) {
                if(mailSendCount == 10) {
                    mailSendCount = 0;
                    try {
                        Thread.sleep(300000);
                    }catch(InterruptedException e) {
                        System.out.println("Exception on Thread Sleep...");
                    }

                }
                int ddr_count = clientDetail.getDdrPendingCount();
                MimeMessage message = generalMailSender.createMimeMessage();
                MimeMessageHelper helper = new MimeMessageHelper(message, true);
                helper.setTo(clientDetail.getMemberEmail().split(","));
                if(clientDetail.getCcMailtoCA() == 1) {
                    helper.setCc(clientDetail.getCcEmail().split(",")); 
                }
                String subject = ddr_count + temp_subject + " : " + clientDetail.getWorkspaceName();
                helper.setSubject(subject);
                helper.setFrom(JGatePropertiesManager.getPropertyValue(PresentationContants.MAIL_USER_NAME));
                Map<String, Object> model = new HashMap<String, Object>();
                model.put("ddr_count", ddr_count > 1 ? "are " + ddr_count : "is " + ddr_count);
                model.put("member_name", clientDetail.getMemberName());
                model.put("from_date", sdf.format(clientDetail.getFromDate()));
                model.put("to_date", sdf.format(c.getTime()));
                String body = VelocityEngineUtils.mergeTemplateIntoString(velocityEngine, "autoDDRPendingMailTemplate.vm", model);
                helper.setText(body, true);
                System.out.println("Sending DDRPending mail to ... " + clientDetail.getMemberEmail());
                String fileName = "DDRPendingAutoMailScheduler.jasper";
                InputStream file = getClass().getResourceAsStream("/com/informatics/jgate2/reports/" + fileName);
                Map<String, Object> parameter_jasper = new HashMap<String, Object>();
                parameter_jasper.put("workspace_id", clientDetail.getWorkspace_id());
                parameter_jasper.put("created_date", sdf.format(new Date()));
                parameter_jasper.put("from_date", sdf.format(clientDetail.getFromDate()));
                parameter_jasper.put("to_date", sdf.format(c.getTime()));               
                DataSource ds = null;
                try {                    
                    JasperPrint jasperPrint = JasperFillManager.fillReport(file, parameter_jasper, connection);
                    ByteArrayOutputStream baos = new ByteArrayOutputStream();
                    JRXlsExporter exporterXls = new JRXlsExporter();
                    exporterXls.setParameter(JRXlsExporterParameter.JASPER_PRINT, jasperPrint);
                    exporterXls.setParameter(JRXlsExporterParameter.IGNORE_PAGE_MARGINS, false);
                    exporterXls.setParameter(JRXlsExporterParameter.IS_COLLAPSE_ROW_SPAN, true);
                    exporterXls.setParameter(JRXlsExporterParameter.IS_WHITE_PAGE_BACKGROUND, false);
                    exporterXls.setParameter(JRXlsExporterParameter.IS_REMOVE_EMPTY_SPACE_BETWEEN_COLUMNS, true);
                    exporterXls.setParameter(JRXlsExporterParameter.IS_REMOVE_EMPTY_SPACE_BETWEEN_ROWS, true);
                    exporterXls.setParameter(JRXlsExporterParameter.IS_DETECT_CELL_TYPE, true);
                    exporterXls.setParameter(JRExporterParameter.OUTPUT_STREAM, baos);
                    exporterXls.exportReport();
                    ds = new ByteArrayDataSource(baos.toByteArray(), "application/excel");                    
                } catch (JRException ex) {
                    Logger.getLogger(JGateMailManagerImpl.class.getName()).log(Level.SEVERE, null, ex);
                }                 
                helper.addAttachment(clientDetail.getWorkspaceName() + "_" +sdf.format(new Date()) + ".xls", ds);
                generalMailSender.send(message);
                mailSendCount++;
                System.out.println("Sent Successfully");
            }
            connection.close();
        } catch (MessagingException ex) {
            Logger.getLogger(JGateMailManagerImpl.class.getName()).log(Level.SEVERE, null, ex);
        } catch (NamingException ex) {
            Logger.getLogger(JGateMailManagerImpl.class.getName()).log(Level.SEVERE, null, ex);
        } catch (SQLException ex) {
            Logger.getLogger(JGateMailManagerImpl.class.getName()).log(Level.SEVERE, null, ex);
           }
    }

发送一系列多封邮件时出现异常：