Default Plesk page not changing

[_James_Clark]

We have a number of domains that we own and that we are hoping to sell to various interested peoples soon. I would like to set it up so that when these pages are visited now, before clients have bought them and started to upload their own content, there is a personal holding page for us as hosts with contact details about potentially buying one of our domains.
I found a file in the Plesk User Guide which seemed to suggest how to do this but when I followed the instructions nothing changed. Is this in fact possible, and if so does anyone know how it can be acheived?

Many thanks