Test SOLIDWORKS PDM SMTP Email Settings Using Windows Telnet Feature

Article by GoEngineer on Mar 17, 2017

In order to send notifications via an SMTP server, the server computer running the SOLIDWORKS PDM Professional database server service must be able to reach and be allowed to relay SMTP commands to the SMTP server. The same applies if you are sending a direct notification by using the (Notify a Colleague) from a client. The client must be able to reach the SMTP server. This article outlines steps for the Windows feature TELNET to test/troubleshoot SMTP notifications.

Note: The steps outlined in this article are intended for IT professionals. Any further assistance will need to be coordinated with IT.


  • Before using this method of troubleshooting, please do both of the following: 
    • Restart the SOLIDWORKS PDM Database Server service 
    • Turn Windows Firewall off 
  • Install the Windows Telnet Client 
    • Control Panel > Programs and Features > Turn Windows features on or off >Telnet client 
  • Only IT or PDM Administrators with windows Administrative access to the server should use this content.


  1. Open Command Prompt by clicking the Windows Start menu. In the search type CMD or Windows Command Processor.
  2. Type ‘telnet <servername><portnumber>.
    1. Example: (telnet mailserver.mycompany.com 25)
  3. If Telnet is successful you will see one of the following responses from your SMTP server with the following message: 
    1. 220 mailserver.mycompany.com Microsoft Exchange Internet Mail Connector
    2. A blank screen with a blinking cursor in the top left-hand corner of the CMD prompt. 
    3. Note: If Telnet fails to contact the SMTP server you will get the following message: Connecting To...Could not open connection to the host, on port 25: Connect failed.
  4. Start communication by typing the following command: EHLO test.com 
    1. Note: You can use the HELO command, but EHLO is a verb that exists in the Extended SMTP verb set that is supported in all current Microsoft implementations of SMTP. It is a good idea to use EHLO unless you believe that there is a problem with the Extended SMTP verbs.
  5. If the command is successful, you receive the following response: 250 OK.
  6. Type the following command to tell the receiving SMTP server who the message is from: MAIL FROM:Admin@test.com 
    • Note: This address can be any SMTP address that you want, but it is a good idea to consider the following issues:
      1. Some SMTP mail systems filter messages based on the MAIL FROM: address and may not allow certain IP addresses to connect or may not allow the IP address to send email to the SMTP mail system if the connecting IP address does not match the domain where the SMTP mail system resides. In this example, that domain is test.com.
      2. . If you do not use a valid email address when you send a message, you cannot determine whether the message had a delivery problem because the non-delivery report (NDR) cannot reach an IP address that is not valid. 
    • If you use a valid email address, you receive the following response from the SMTP server: 250 OK - MAIL FROM Admin@test.com
  7. Type the following command to tell the receiving SMTP server the address that the email message is being sent to: RCPT TO: User@Domain.Com
    1. You receive the following response: 250 OK - Recipient User@Domain.Com
    2. Note: It is a good idea to always use a valid recipient SMTP address in the domain that you are sending email to. For example, if you are sending to john@domain.com, you must be certain that john@domain.com exists in the domain. Otherwise, you will receive an NDR.
  8. Type the following command to tell the SMTP server that you are ready to send data: DATA
    1. You receive the following response: 354 Send data. End with CRLF.CRLF 
  9. Now that the DATA command has been sent we can start sending the message contents. This starts with the various headers. At a minimum, a message should contain a To, From, Subject, and Date Header. The headers entered here will be shown to the user in their email client.
    1. Type the following command to add a subject line: Subject: test message
  10. Press Enter two times. You do not receive a response from this command.
  11. Type the following command to add message body text: This is a test message you will not see a response from this command.
  12. Type a period (.) at the next blank line, and then press Enter. You receive the following response: 250 Received
  13. Close the connection by typing the following command: QUIT
    1. You receive the following response: 221 closing connection.
  14. Verify that the recipient received the message that you sent. If any error event messages occur in the application event log, or if there are problems receiving the message, check the configuration or the communication to the host.  

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