How can I test an SMTP connection from the Hosting Control Panel?

The SMTP Tester checks an SMTP service from your website's assigned Windows web server. You can use it to troubleshoot DNS resolution, the network connection, SSL/TLS negotiation, SMTP authentication, and whether the server accepts a sender and recipient.

The SMTP Tester is currently available for Windows hosting plans only.

Open the SMTP Tester

1. Sign in to your Hosting Control Panel.
2. Select WEBSITES, then select Websites.
3. Find the website from which you want to run the test and select More Functions.
4. Under Application & Runtime, select SMTP Tester.

Test an email service hosted by us

1. For Is the SMTP service hosted by us?, select Yes.
2. Select an activated email domain from the hosting plan.
3. Select the connection security: SSL/TLS with STARTTLS, SSL/TLS (implicit), or No SSL.
4. To verify an email account's credentials, select Test SMTP login and enter the complete email address as the username and its password.
5. To check whether the server accepts a sender and recipient, select Test sender and recipient acceptance and enter both email addresses.
6. Select Run SMTP Test.

The control panel automatically selects the SMTP server and port for the chosen hosted email domain and security mode.

Test an external SMTP service

1. For Is the SMTP service hosted by us?, select No, it is an external SMTP service.
2. Enter the SMTP hostname. Enter a host name such as smtp.example.com, not a website URL.
3. Select port 25, 465, 587, or 8889.
4. Select the connection security required by the SMTP provider: SSL/TLS with STARTTLS, SSL/TLS (implicit), No SSL, or Automatic.
5. Optionally select Test SMTP login and enter the SMTP username and password.
6. Optionally select Test sender and recipient acceptance and enter the sender and recipient email addresses.
7. Select Run SMTP Test.

Understand the results

The Test results section shows each diagnostic stage as passed, failed, or another reported status. Depending on the selected options, the stages can include DNS lookup, TCP connection, SSL/TLS negotiation, SMTP login, and sender or recipient acceptance. Review the message and SMTP response shown for the first failed stage.

The sender and recipient acceptance check does not send an email message. It checks whether the SMTP server accepts the supplied envelope addresses during the SMTP conversation.

Important notes

• Run the test from the website that is experiencing the SMTP problem. The connection originates from that website's assigned Windows web server.
• Use the same SMTP hostname, port, security mode, and credentials as your application whenever possible.
• A successful connection or recipient-acceptance test does not guarantee inbox delivery. Spam filtering, message content, sender authentication, reputation, and the recipient's mail system can still affect final delivery.
• Do not send your SMTP password to Support. If you need assistance, provide the failed stage, its response, the SMTP hostname and port, and the approximate test time.