Use Telnet to Diagnose PSQL Communication & Port Disabling Problem

Release Date: 08/02/2021

If you are running Elliott directly on the PSQL server console, and Elliott suddenly stops working and displays a file access error like 3XXXX for the SYSPASS.BTR file on a workstation while it is working, it is an indication of a network error. If this error is consistent, then it is likely because there's some kind of TCP port blocking the PSQL communication traffic. The likely causes could be:
  • The Windows Server firewall is turned on -- This could be the result of configuring the role of the server  to be a "public" server, which will cause the Windows server OS to tightly control the allowed port number access.  Often the installation of a service pact update can cause an issue like this.
  • Anti-Virus Software -- The anti-virus software can block network traffic communication and cause similar issues.
  • Physical Firewall -- If a physical firewall is installed and a configuration is changed, it can block the network traffic for PSQL.
PSQL TCP Port Number
The best way to diagnose and confirm if the network traffic is blocked is to use the Telnet utility to confirm.  PSQL uses the following two port numbers to communicate, and we need to make sure they are not blocked:
  • 1583
  • 3351
Use Telnet to Check If PSQL Port Number Is Open
For example, you could use the following command prompt:
    Telnet IP-address 1583
where IP-address is the PSQL server IP address like
  • If the command prompt screen becomes blank, that means the port is open and a connection is made. To exit, you can simply close the command prompt window.
  • If the command prompt screen does not change and looks as if it is stuck, then eventually times out with an error, that means the port is not open. See sample screen below.

Should Netcellent Support Look into the Port Number Problem?
It is important to know whether the PSQL issue is due to the port opening problem to determine who you should talk to.  Netcellent support cannot resolve it for you if the necessary ports for PSQL on the server or client are not open. You will need to get your IT support for a proper solution.  On the other hand, if the port is open and PSQL is not working, that it is something Netcellent support should look into further.

Enable Telnet Client
Just FYI, Telnet utility is not installed by default.  To install it, go to the bottom left corner of your desktop and choose "Search," then type "Turn Windows features on or off." See sample screen below:

In Windows Features, find "Telnet Client" and check it to install. See sample screen below:


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