Alexander, It appears that you are using the old SQL Toolkit. This toolkit uses 3rd party ODBC drivers and you can only connect to a database using the ODBC Administrator and defining a DSN.
The article you read about connection strings refers to the Database Connectivity Toolkit, which uses Microsoft's ActiveX Data Objects to communicate with databases. Those connection strings and the Data Links that Herbert describes only work with this Toolkit - released in 2001 and works with every version of LabVIEW from 6.0 to 7.1.
