Admin login problem exist after installation in magento?

Hi All,

Use the following URL to login 

http://localhost/magento/index.php/admin 

if does not work then use the another way to login 

OR 

Open Varien.php file using the following path: 

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

find the below given code in above file:
if (isset($cookieParams['domain'])) {
    $cookieParams['domain'] = $cookie->getDomain();

}

Replace If condition with the below if condition:

if (isset($cookieParams['domain']) && !in_array("127.0.0.1", self::getValidatorData())) {

And done!

Cheers!