To get a working connection to the SQL database, the SQL Server should be up and running.
Second, the SQL Server should allow SQL Server Authentication. This is the authentication method used by Dynamic AI to connect to the database server.
This option can be controlled from the SQL Management Studio which is provided with the SQL database server and usually installed on the same machine.
A free edition, SQL Management Studio Express, is downloadable from Microsoft.com.
The Management studio can be especially helpful when attaching databases - e.g.: the sample database Adventureworks available from Microsoft.
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