[UKBusinessLive]

have you a backup made of your site, normally they just change the index.php file, Change this first and see, but if you do regular backups of your server, then upload this backup and you'll find everything will be OK. You need to double check all your FTP accounts and change your Passwords, Also make sure of the types of uploads members can do.

These types of hacking often happen when a hacker uploads a piece of code in the gist of an image

good luck with the backup, or if you have an index.php file add that first see what happens

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