Magento Can't able to login in admin

Some time After the installation of magento we can't able to login in admin and we stuck that we have not installed Properly generically while installing some of the permission is required which is not available and so we need to edit one file



Go to app/code/core/Mage/Core/Model/Session/Abstract/Varien.php file within your magento directory.
For Magento 1.4-1.5 Version
Find the code:

session_set_cookie_params(

$this->getCookie()->getLifetime(),

$this->getCookie()->getPath(),

$this->getCookie()->getDomain(),

$this->getCookie()->isSecure(),

$this->getCookie()->getHttponly()

);

and replace with

session_set_cookie_params(

$this->getCookie()->getLifetime(),

$this->getCookie()->getPath()

//$this->getCookie()->getDomain(),

//$this->getCookie()->isSecure(),

//$this->getCookie()->getHttponly()

);

For Magento < 1.6 Version
Find the code:

$cookieParams = array(

            'lifetime' => $cookie->getLifetime(),

            'path'     => $cookie->getPath(),

            'domain'   => $cookie->getConfigDomain(),

            'secure'   => $cookie->isSecure(),

            'httponly' => $cookie->getHttponly()

        );

and replace with

$cookieParams = array(

            'lifetime' => $cookie->getLifetime(),

            'path'     => $cookie->getPath(),

           // 'domain'   => $cookie->getConfigDomain(),

           // 'secure'   => $cookie->isSecure(),

          // 'httponly' => $cookie->getHttponly()

        );

We have commented few lines
After this save the file.clear the cache and  And try to login into the admin.