php联接sql server 2008连不上呀

<br /><?php<br />/* Specify the server and connection string attributes. */<br />$serverName = "(local)";<br />$connectionInfo = array( "Database"=>"myDB1");<br /><br />/* Connect using Windows Authentication. */<br />$conn = sqlsrv_connect( $serverName, $connectionInfo);<br />if( $conn === false )<br />{<br />     echo "Unable to connect.</br>";<br />     die( print_r( sqlsrv_errors(), true));<br />}<br />else<br />     echo "great! </br>";<br />?><br />