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: This documentation is for Moodle 2.7. For up-to-date documentation see 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.