How to hide set from mail on php mail

When sending an email using PHP's mail() function, you can hide the Set-Cookie headers by setting the P3P header in your email. Here's an example:

$headers = array(
    'From' => '[email protected]',
    'Subject' => 'Test Email',
    'P3P' => 'CP="NOI ADM DEV PSAi COM NAV OUR STP MIE SAM OTRo STPo DES DEVa TMT ENG TEA STA PRE"',
);

mail('[email protected]', 'Test Email', 'Hello, world!', $headers);

The P3P header is a way to specify the privacy policy of your website, and by setting it to CP="NOI ADM DEV PSAi COM NAV OUR STP MIE SAM OTRo STPo DES DEVa TMT ENG TEA STA PRE", you're telling the email client that your website does not set cookies.

However, please note that this method is not foolproof, as some email clients may still display the Set-Cookie headers even with the P3P header set.

Alternatively, you can use a PHP library like SwiftMailer or PHPMailer which provide more advanced features for sending emails, including the ability to hide cookies.

Here's an example using SwiftMailer:

$mailer = new Swift_Mailer(new Swift_SendmailTransport());

$message = Swift_Message::newInstance('Test Email')
    ->setFrom('[email protected]')
    ->setTo('[email protected]')
    ->setBody('Hello, world!')
    ->setContentType('text/plain');

$message->getHeaders()->addTextHeader('P3P', 'CP="NOI ADM DEV PSAi COM NAV OUR STP MIE SAM OTRo STPo DES DEVa TMT ENG TEA STA PRE"');

$mailer->send($message);

And here's an example using PHPMailer:

$mail = new PHPMailer();

$mail->setFrom('[email protected]');
$mail->addAddress('[email protected]');
$mail->Subject = 'Test Email';
$mail->Body = 'Hello, world!';

$mail->addCustomHeader('P3P', 'CP="NOI ADM DEV PSAi COM NAV OUR STP MIE SAM OTRo STPo DES DEVa TMT ENG TEA STA PRE"');

$mail->send();

Keep in mind that hiding cookies may not be necessary or desirable in all cases, and you should carefully consider the implications of doing so.