Message could not be sent.Mailer Error:

Guys i am now working with php mailer library.i have some errors related to mail() functions. This my source code

<?php
require 'class.phpmailer.php';

$mail = new PHPMailer;

$mail->IsSMTP();                                      // Set mailer to use SMTP
$mail->Host = 'smtp.google.com';                 // Specify main and backup server
$mail->Port = 587;                                    // Set the SMTP port
$mail->SMTPAuth = true;                               // Enable SMTP authentication
$mail->Username = '[email protected]';                // SMTP username
$mail->Password = '8903273610';                  // SMTP password
$mail->SMTPSecure = 'tls';                            // Enable encryption, 'ssl' also accepted

$mail->From = '[email protected]';
$mail->FromName = 'VENKAT';
$mail->AddAddress('[email protected]', 'Josh Adams');  // Add a recipient
$mail->AddAddress('[email protected]');               // Name is optional

$mail->IsHTML(true);                                  // Set email format to HTML

$mail->Subject = 'Here is the subject';
$mail->Body    = 'This is the HTML message body <strong>in bold!</strong>';
$mail->AltBody = 'This is the body in plain text for non-HTML mail clients';

if(!$mail->Send()) {
   echo 'Message could not be sent.';
   echo 'Mailer Error: ' . $mail->ErrorInfo;
   exit;
}

echo 'Message has been sent';

THIS SHOWs ME A ERROR MESSAGE Message could not be sent.Mailer Error: The following From address failed: [email protected] : Called Mail() without being connected

At before i use this source code before but i don't have the vendor/autoload file in my phpmailer folder but i download this file in Github

<?php
/**
 * This example shows settings to use when sending via Google's Gmail servers.
 * This uses traditional id & password authentication - look at the gmail_xoauth.phps
 * example to see how to use XOAUTH2.
 * The IMAP section shows how to save this message to the 'Sent Mail' folder using IMAP commands.
 */
//Import PHPMailer classes into the global namespace
use PHPMailer\PHPMailer\PHPMailer;
require '../vendor/autoload.php';
//Create a new PHPMailer instance
$mail = new PHPMailer;
//Tell PHPMailer to use SMTP
$mail->isSMTP();
//Enable SMTP debugging
// 0 = off (for production use)
// 1 = client messages
// 2 = client and server messages
$mail->SMTPDebug = 2;
//Set the hostname of the mail server
$mail->Host = 'smtp.gmail.com';
// use
// $mail->Host = gethostbyname('smtp.gmail.com');
// if your network does not support SMTP over IPv6
//Set the SMTP port number - 587 for authenticated TLS, a.k.a. RFC4409 SMTP submission
$mail->Port = 587;
//Set the encryption system to use - ssl (deprecated) or tls
$mail->SMTPSecure = 'tls';
//Whether to use SMTP authentication
$mail->SMTPAuth = true;
//Username to use for SMTP authentication - use full email address for gmail
$mail->Username = "[email protected]";
//Password to use for SMTP authentication
$mail->Password = "yourpassword";
//Set who the message is to be sent from
$mail->setFrom('[email protected]', 'First Last');
//Set an alternative reply-to address
$mail->addReplyTo('[email protected]', 'First Last');
//Set who the message is to be sent to
$mail->addAddress('[email protected]', 'John Doe');
//Set the subject line
$mail->Subject = 'PHPMailer GMail SMTP test';
//Read an HTML message body from an external file, convert referenced images to embedded,
//convert HTML into a basic plain-text alternative body
$mail->msgHTML(file_get_contents('contents.html'), __DIR__);
//Replace the plain text body with one created manually
$mail->AltBody = 'This is a plain-text message body';
//Attach an image file
$mail->addAttachment('images/phpmailer_mini.png');
//send the message, check for errors
if (!$mail->send()) {
    echo "Mailer Error: " . $mail->ErrorInfo;
} else {
    echo "Message sent!";
    //Section 2: IMAP
    //Uncomment these to save your message in the 'Sent Mail' folder.
    #if (save_mail($mail)) {
    #    echo "Message saved!";
    #}
}
//Section 2: IMAP
//IMAP commands requires the PHP IMAP Extension, found at: https://php.net/manual/en/imap.setup.php
//Function to call which uses the PHP imap_*() functions to save messages: https://php.net/manual/en/book.imap.php
//You can use imap_getmailboxes($imapStream, '/imap/ssl') to get a list of available folders or labels, this can
//be useful if you are trying to get this working on a non-Gmail IMAP server.
function save_mail($mail)
{
    //You can change 'Sent Mail' to any other folder or tag
    $path = "{imap.gmail.com:993/imap/ssl}[Gmail]/Sent Mail";
    //Tell your server to open an IMAP connection using the same username and password as you used for SMTP
    $imapStream = imap_open($path, $mail->Username, $mail->Password);
    $result = imap_append($imapStream, $path, $mail->getSentMIMEMessage());
    imap_close($imapStream);
    return $result;
}
    enter code here

Solution

Try adding the below code,

use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\Exception;

require 'PHPMailer/src/Exception.php';
require 'PHPMailer/src/PHPMailer.php';
require 'PHPMailer/src/SMTP.php';