error/forum/nopostforum
From MoodleDocs
You are trying to post in a forum that you are not allowed to post into and the language text for the error message is missing from the language files.
Note: You are currently viewing documentation for Moodle 3.2. Up-to-date documentation for the latest stable version of Moodle is probably available here: error/forum/nopostforum.
You are trying to post in a forum that you are not allowed to post into and the language text for the error message is missing from the language files.