In the case where you have a SQL Server 2005 Express Edition database, you need to do a couple of things: Right-click the Server Explorer window, select Connect to Server... and then select Server from the Connect to Server drop down box. Select SQL Server Database [Northwind] from the Connect to Server drop down list.
The Data Source=... like shown in the output window, has been added, which means that ADO.NET is now able to locate the Northwind database. Note that on the Connection tab, the server name has been added, as well as the database name. Also note the field Database that has been added in the Connection tab. This makes the connection to the Northwind database context-sensitive.
In the Options tab, note the Internal Data Provider (the standard Microsoft Data Provider), the SQL Server connection string and the Connection String for Oracle connection string.
Since ADO.NET already contains the SQL connection string information for the server name and database, no additional connection string needs to be added to the data source for the database connection. d2c66b5586