Note: You are currently viewing documentation for Moodle 3.0. Up-to-date documentation for the latest stable version of Moodle may be available here: error/question/missingimportantcode.

error/question/missingimportantcode

From MoodleDocs

The question code is expecting to find some code that is not there. It is most likely that you have installed an optional question plugin that is not compatible with this version of Moodle. Check with the plugin author to see if a newer version exists.