Error "Rejected request from RFC1918 IP to public server address" on FileMaker WebDirect

[Selva]

Dear All,

We have installed FileMaker Server 18. We have added a custom SSL certificate to FileMaker Server 18. On FileMaker Pro, we can view the green encrypted symbol and can able to access the Server DB. But on FileMaker WebDirect, we can't open the Server DB using the Domain name. We have received the error "No such file or directory" on connecting externally. On the internal network, we have received the error "Rejected request from RFC1918 IP to public server address" when we opening the WebDirect using Domain name.

Can anyone help us to solve this issue?

Thanks.