Problem Description:

After installing ShowCase server patch, users are unable to connect. One of the following errors are displayed:

ShowCase IBM i Driver Error connecting to server 'svs4vs24:43435': Connection refused to host:; nested exception is: Connection refused: connect. [ OK ]
ShowCase Query  - 1 table(s) must be Change Linked to make the query executable [ OK ] [Cancel ]

Following the change-link dialog, the following displays:

ShowCase Query java.lang.NullPointerException [ OK ]
ShowCase IBM i Driver Server 'SVS4VS24:43438' not available. [ OK ]


Issue was resolved by:

  1. End the Showcase server
  2. Run the RMVSCTCP command with option Force Remove=*YES
  3. Run the ADDSCTCP and select different ports than used before


The errors are caused by communication problems related to the ports. In some cases, it's very difficult to determine if a specific port is blocked or in use on your network, and it's easier to simply select different ports.

The port affected generates a different error. The specific port can be identified, based on the error received by the user:

  • " Connection refused: connect." (Firewall port)
  • "1 table(s) must be Change Linked to make the query executable" (Compression port)
  • "Server 'system:port' not available." (Server port)

Watch the video below for more information.

Still have questions? We can help. Submit a case to technical support

Last Modified On:
You don't have the appropriate permissions.
No, open a new Support Case