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

In fact there is no programming and set up issues for this problem.

1. Find this code snipet from Varien.php and replace as below

   if ((isset($cookieParams['domain'])) && !in_array("127.0.0.1", 
         self::getValidatorData())) {
         $cookieParams['domain'] = $cookie->getDomain();
   }
   

2. Just open another browser and open the local magento page with 127.0.0.1 instead of localhost.

3. Clear the browser history with cookie for good practice.