Getting an error that i don't know how to fix [duplicate]

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• PHP mail form doesn't complete sending e-mail 22 answers

Why am i getting a mail() error failed to connect to mail server? How can i fix it? I've tried almost everything i could think of. Thank you for your help!

<?php
if (isset($_POST["forgotPass"])) {
    $connection = new mysqli("localhost", "root", "", "membershipsystem");

    $email = $connection->real_escape_string($_POST["email"]);

    $data = $connection->query("SELECT id FROM users WHERE email='$email'");

    if ($data->num_rows > 0) {
        $str = "0123456789qwertyuiopasdfghjklzxcvbnm";
        $str = str_shuffle($str);
        $str = substr($str, 0, 10);
        $url= "http://ift.tt/2sI7dLR?
token=$str&email=$email";

        mail($email, "Reset Password", "To reset your password, please visit 
this: $url", "From: example.com\r\n");

        $connection->query("UPDATE users SET token='$str' WHERE 
email='$email'");

        echo "Please check your email!";
    }else{
        echo "Please check your inputs!";
    }

}
?>