We have noticed that when a user tries to access an Enterprise Site that they don’t have permission to view yet it redirects them to a non-descript page. As seen below.
We wanted to know if is this by design or not and if there was a specific config or HTML page we could update that would allow us to provide more contextual information. (i.e. "You don’t have permission to view this site..please contact <email address>").
Which version are you on? On my 10.9.1 test site, if an anonymous user tries to view it without login, the default page that is shown to user informs them that login is required.
When an authenticated user, even with admin role, that do not have permission to view the site, the following is shown:
Hope it helps.