Not able to see a node under 'Untrusted nodes' tab in the TIBCO Spotfire Server Admin UI

Product:TIBCO Spotfire Server
Versions:7.5 and higher

Summary:
This article describes a case where after installing a Node Manager, it doesn't show up in the 'Untrusted nodes' tab in the TIBCO Spotfire Server Admin UI

Details:
In Spotfire version 7.5 and higher, after installation of TIBCO Spotfire Server and Node manager, the Spotfire Server and the Node manager services are started up but you can't see the node under 'Untrusted nodes' to trust.

Below errors message appears multiple times in the server.log file.
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Error updating database.  Cause: com.microsoft.sqlserver.jdbc.SQLServerException: The INSERT statement conflicted with the FOREIGN KEY constraint "FK_NODES_SITE_ID". The conflict occurred in database "<DB name>", table "dbo.SITES", column 'SITE_ID'.
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Resolution:
  
>> Check if any invalid node is listed in the Spotfire database by running the below command, refer below screenshot.
 

<Spotfire Server install dir>\tomcat\bin\config list-nodes

>> If you see any nodes which are invalid (Has Valid Node ID = No), you can delete the nodes by using the 'config delete-node' command.
e.g.

<Spotfire Server Install>\tomcat\bin\config delete-node --id=<id of the node that should be deleted>

>> Restart the Spotfire Server service and Node Manager service.