The TCP/IP connection to the host localhost, port 1433 has failed. Error: "Connection refused: connect. Verify the connection properties, check that an instance of SQL Server is running on the host and accepting TCP/IP connections at the port, and that no firewall is blocking TCP connections to the port.
Tjek din SQL Server-indstilling tillader accept af TCP/IP-forbindelser. Aktiver TCP/IP og genstart SQL Server. Test derefter din kode igen.
