The Discovery Wizard locates and displays the SQL Servers on the network that you may want the Diagnostic Server to monitor. If the wizard discovers no instances of SQL Servers on the network, one reason may be that the SQL Server components that enable Spotlight to discover those servers have not been installed. See "Install SQL Server Client Tools" in the online help for Microsoft SQL Server for more information. The SQL Server Client Tools are on the installation disk for Microsoft SQL Server 2000, 2005, and 2008. This information is also present in the getting started guide that can be downloaded from Quest Support Portal:
https://support.quest.com/searchdocumentation.aspx?pr=268441978