The last code
define('YS_DB_NAME', $db_name); // The name of the database used by the board
define('YS_DB_HOST', $db_server); // The name of the database server
define('YS_DB_USERNAME', $db_user); // The username to use to connect to the database
define('YS_DB_PASSWORD', $db_passwd); // The password to use to connect to the database
// The web path to your YaBB SE Board directory
// In this example http://yoursite_name.com/yabbse/
define('YS_WEB_PATH', 'http://perch/yabbse/');
// The Name of the Cookie used for YaBBSE logon
define('YS_COOKIE_NAME', $cookiename);
// Prefix for the database tables
define('YS_TABLE_PREFIX', $db_prefix); // Table Prefix
And my news code
define('YS_DB_NAME', 'yabbse'); // The name of the database used by the board
define('YS_DB_HOST', 'localhost'); // The name of the database server
define('YS_DB_USERNAME', 'root'); // The username to use to connect to the database
define('YS_DB_PASSWORD', ''); // The password to use to connect to the database
// The web path to your YaBB SE Board directory
// In this example http://yoursite_name.com/yabbse/
define('YS_WEB_PATH', "$boardurl/");
// The Name of the Cookie used for YaBBSE logon
define('YS_COOKIE_NAME', 'YaBBSE155');
// Prefix for the database tables
define('YS_TABLE_PREFIX', 'yabbse_'); // Table Prefix
Then the part of the code which poses problem is as follows but I do not see what it is necessary to do to correct or make function this script
// ------------------------------------------------------------------------- //
// Define wheter we can join tables or not in SQL queries (same host & same db or user)
define('UDB_CAN_JOIN_TABLES', (YS_DB_HOST == $CONFIG['dbserver'] && (YS_DB_NAME == $CONFIG['dbname'] || YS_DB_USERNAME == $CONFIG['dbuser'])));
// Connect to YaBB SE Database if necessary
$UDB_DB_LINK_ID = 0;
$UDB_DB_NAME_PREFIX = YS_DB_NAME ? '`' . YS_DB_NAME . '`.' : '';
if (!UDB_CAN_JOIN_TABLES) {
$UDB_DB_LINK_ID = @mysql_connect(YS_BD_HOST, YS_DB_USERNAME, YS_DB_PASSWORD);
if (!$UDB_DB_LINK_ID) die("<b>Coppermine critical error</b>:<br />Unable to connect to YaBB SE Board database !<br /><br />MySQL said: <b>" . mysql_error() . "</b>");
}