When using a multitier configuration (frontend-backend, balancer) you have to ensure that a correct client IP address is passed on to the web project, which can be achieved by setting an appropriate HTTP header field (X-Real-IP, X-Forwarded-For) on a balancer or caching proxy server and then having a web server (in mod_rpaf etc.) or web application to get this value.

- Open "Settings > Tools > PHP Settings" and check the value of _SERVER["REMOTE_ADDR"]. It must be set to your IP address. You can also view this value in "Settings > Proactive protection > Control Panel Protection".