The administrator of the forum page sets permissions, decides who can view the forum and who can post in it. Some forums are restricted to people who are signed in. Others might be restricted to specific groups, such as all staff and students in a particular department.
If you try to access a forum that you do not have permission to access, you see a message similar to the following:
You are already signed in with username [your username] but do not have permission to view this page. If you believe this is an error, please contact the IT Services Help Desk.
If you believe you should have access to the forum, please try to contact the forum administrator (if you know who that is) or email them via the page contact cited at the bottom left of the page.
Email webteam at warwick dot ac dot uk
How to report a problem