That message can be caused by the wrong permissions (if you host runs phpsuexec) or an error in your .htaccess file. Try looking for anything with 777 permissions, and temporarily rename your .htaccess to see if that fixes it.

HTH .

If you have a backup of everything from your site on your PC (and by everything I mean the files, folders, structure), then just FTP the whole thing back from your hosting providers control panel. It should be OK.

If not, you may have to delete the current database you're using, reinstall the base application (if WP or Joomla or a forum app), and completely start over again.

You may be able to ask you hosting provider if they have a backup they can restore. They should, but they'll most likely charge you $100+ to do this.

Best of luck. I've been here, sometimes its just better to blow the whole thing out and re-post whatever you have backed up.

Lesson for everyone: Make multiple backups in multiple save locations!

A lession for everyone,backup your blog's content.But how can I backup a blog? Please kindly help with this.

If you're looking for a backup plugin for WP, here's a link that shows 10 different options available.

Top 10 Best WordPress Backup Plugins, Services Review

You can also backup the whole wordpress site with single click by using this plugin WPTwin on Wp Twin