I try to explain. I have SQL Server 2012 installed as a default instance and SQL Server 2014 installed as a named instance. I have the latest JIRA + Service Desk version running on a Tomcat. If I connect JIRA to SQL Server 2012 then works well. If I try to connect it with the 2014 one, doing exactly what this page says then it gives a connection refused error. Even I have cared of configuring SQL Server 2014 to run on an static TCP port instead of on a dynamic as it was by default. For that purpose I used the configuration tool that came out of the box with my SQL Server 2014.
What am I doing differently?