I can no longer log into Drupal 7's admin area after adding SSL certificate and forcing HTTPS in url. 

The website was previously served via HTTP protocol and worked perfectly fine. I would also like to mention that if I revert back to HTTP mode, the site will work as expected. However, I am trying to implement HTTPS.

Additionally, while logging in, I have noticed that the cookie response would be sent by the server but it would get deleted immediately leading to access denied message.

So far, after going through mixed response in the internet, I have played around with session.cookie, $base\_url and $cookie\_domain variables within settings.php file. I haven't found a solution yet.

Has anyone bumped into this problem? Your response will be highly appreciated.