Phill Edwards wrote: > I can see these errors in /usr/local/tomcat/logs/catalina.out: > > Unable to instantiate DB connection pool. > Technical error message: > java.lang.NullPointerException > A null connection was relinquished. > > Does that shed any more light on the matter? Err, yes. As the message suggests, your Tomcat server cannot create the connection pool which it makes available to the web applications it runs. You need to check $CATALINA_HOME/conf/Catalina/localhost/${your-app-name}.xml or the deployment descriptor in the application codebase at /META-INF/server.xml (both of these paths are from memory). In there you should find a <Resource>...</Resource> element with the connection parameters, including username, password and the JDBC driver class. You should check that the Driver classname is correct for the JDBC jar you're using.