Admin Login not working in magento

Solution is, go to the following page and command the lines as per following instruction.

app\code\core\Mage\Core\Model\Session\Abstract\Varien.php

        // session cookie params
        $cookieParams = array(
            'lifetime' => $cookie->getLifetime(),
            'path'     => $cookie->getPath()
            /*'domain'   => $cookie->getConfigDomain(),
            'secure'   => $cookie->isSecure(),
            'httponly' => $cookie->getHttponly()*/
        );

By Avenir Team