Magento can't login in admin with right username and password

Question

I just freshly installed Magento(1.7.0.2) on my localhost(LAMP). Now after installation when I wanted to go for the admin panel it asked me for the username and

Answer 1

1.Open Varien.php file Location app\code\core\Mage\Core\Model\Session\Abstract.

2.Find and comment the bellow code

if (!$cookieParams['httponly']) {
       unset($cookieParams['httponly']);
       if (!$cookieParams['secure']) {
           unset($cookieParams['secure']);
           if (!$cookieParams['domain']) {
               unset($cookieParams['domain']);
           }
       }
   }

   if (isset($cookieParams['domain'])) {
       $cookieParams['domain'] = $cookie->getDomain();
   }

Source http://infynet.wordpress.com/2013/07/17/admin-login-fail-in-magento/