SMTP Troubleshooting Sending Email Alerts and Logs

Below is a list of strategies to troubleshoot SMTP settings. If sending email alerts or logs fails, the first step is to examine the error message. Most of the time, the error message helps narrow down the cause of the error; however, most of the time the following checklist should be used to systematically pinpoint what the may be causing the email failure:

  • Check internet connectivity on the machine where you are trying to send the email
  • Check the SMTP host name / address
  • Check email addresses are entered correctly
  • Check SMTP user name and password
  • Check whether the SMTP server requires TLS/SSL/STARTTLS
  • Check whether the port your entered is supported by the SMTP server. Also make sure the server supports the TLS/SSL setting on the port you entered
  • See if other applications on the same machine can access the same SMTP server with the exact same settings
  • Try turning off antivirus and other security software which may be blocking outbound traffic
  • Check firewall settings. The firewall might be configured to block outbound traffic
  • Some ISPs are blocking certain ports, especially SMTP related ports in order to prevent spam. For that reason, many SMTP servers offer alternative ports, such as port 80
  • If you are using a public email service, like Gmail or Yahoo, you will need to change the settings in your account to specifically allow SMTP traffic, see Gmail SMTP Configuration for Backup Alerts
  • Note that many SMTP servers will automatically ban your IP if several logon attempts have failed within a certain time. You may have to wait up to half an hour and try again
  • In many corporate networks the internet routers are configured to block outbound traffic. Please check router settings to ensure the connection isn’t blocked
  • Try other SMTP servers and see if a connection can be made using the same outbound port
  • DNS failures: try pinging the SMTP address and see if it resolves correctly
  • Proxy servers: does your network require outbound traffic to go through a proxy?
  • If the test is successful but the email doesn’t show up in the mailbox, check the spam filter settings or junk mailbox on the account