Is it hosted on your Webhosting or through Prestashop? Which version of PHP and PS are you running? I honestly don't think it's a hacker. He would be posting some other crap instead of a 403. If you can Access the Data File System, you can check the .htaccess file if IPs have been blocked or if the folder permission has been changed. If you are unsure, contact your hosting provider for support.
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Is it hosted on your Webhosting or through Prestashop? Which version of PHP and PS are you running? I honestly don't think it's a hacker. He would be posting some other crap instead of a 403. If you can Access the Data File System, you can check the .htaccess file if IPs have been blocked or if the folder permission has been changed.
Is it hosted on your own Webhosting or through Prestashop? Which version of PHP and PS are you running?