To resolve it, follow the below steps:
1) Stop the Spotfire Server Service and remove all the mentioned JDBC driver(s) -> SQLJDBC4.Jar and mssql-jdbc.jar from the below folder(s) of the TIBCO Spotfire Server Installation Directory: \tomcat\lib,\tomcat\custom-ext,\tomcat\spotfire-lib and \tomcat\webapps\spotfire\WEB-INF\lib
Note: Take the backup of the driver(s) which are being removed.
2) Download the 'sqljdbc42.jar' driver from the link:
https://www.microsoft.com/download/details.aspx?id=11774 or 'mssql-jdbc-8.2.2.jre8.jar' from the link:
https://docs.microsoft.com/en-us/sql/connect/jdbc/download-microsoft-jdbc-driver-for-sql-server?view=sql-server-ver153) Place the driver inside the \tomcat\custom-ext folder and restart the Spotfire Server Service.