My Sql Connection Problem in WAMP SERVER2

As @ssusanta reported, WAMP Server2 is installed but PHP code cannot connect to MySQL. Common root causes are: the MySQL service is not running, the PHP MySQL extension is not enabled (or the PHP version no longer supports mysql*), wrong host/credentials, or a port/socket mismatch. @nav33n's point about the exact error message is critical — different messages point to different fixes (authentication vs server not listening vs missing extension). @servis is correct that network rules matter for remote connections, but local PHP scripts usually fail for service/extension reasons.

Practical diagnostics (no external links required to follow these steps):

• Confirm MySQL is running (WAMP tray icon or Windows Services) and port 3306 is listening.
• From the server shell try mysql -u root -p to verify credentials and that the server accepts connections.
• Create a short file with <?php phpinfo(); ?> and open it in the browser; search the output for mysqli or pdo_mysql to ensure a driver is loaded.
• If the error is Call to undefined function mysql_connect(), enable the appropriate PHP extension or migrate away from deprecated mysql_* functions.

A modern, robust example uses PDO with exceptions and proper charset:

<?php
try {
    $pdo = new PDO('mysql:host=127.0.0.1;dbname=your_db;charset=utf8mb4', 'root', '', [
        PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
    ]);
    echo 'Connected';
} catch (PDOException $e) {
    echo 'Connection failed: ' . $e->getMessage();
}
?>

For further, authoritative reference see the PHP PDO documentation (PDO connections) and WampServer official site (WampServer).