The Help Centre includes information on many different subjects. Some of this information is fine for public consumption (like this article), some is good for registered customers only, and some is for GNS Staff.
Whether you're registered and logged in, or not, will determine what information you can see. If you are a customer or staff member of GNS, click the 'Sign in' button in the top right of this page to access all the information relevant to you.
For more information on accessing restricted content, see this article.