Website hacked, need immediate help

"Forbidden

You don’t have permission to access / on this server."

My website has been hacked & now getting this message. No front / back end is been accessible. When i typed the url in browser getting the above message.

What could be the reason & what needs to be done to prevent it & make the website immediately?

  1. Contact your hosting provider and ask them to investigate.
  2. Ask them to change access passwords
  3. Get your last backup
  4. Scan computers from where uploads/updates/manipulations to your website are usually performed, to make sure they are not infected.
  5. Find someone with enough knowledge and whom you trust to analyze and repair your site (a good candidate might be the guy who developed it, someone with GIAC certification might be better, but let’s be realistic :))

The following links might help:
http://brian.teeman.net/tips-and-tricks/help-my-joomla-web-site-has-been-hacked.html
http://codex.wordpress.org/FAQ_My_site_was_hacked
http://www.seochat.com/c/a/Search-Engine-Optimization-Help/Has-Your-Website-Been-Hacked/