I am still receiving this same error. It is consistent. It can only be resolved by logging out.
When I log out I can view the forums. When I log in I cannot.
The only way for me to post is to log out, navigate to the post I want to reply to, hit the reply button, and then log in from there and continue, after which I must log out again to view the forums.
It appears Cadence tests their web site as well as they test their software.