Hi Nicolas, the database schema in Moodle 4.0 changed from that of Moodle 3. You need to be running CodeRunner 5.0 or later with Moodle 4.0. CodeRunner V5.1.1 is available either from GitHub (https://github.com/trampgeek/moodle-qtype_coderunner) or the Moodle plugin repository (https://moodle.org/plugins/qtype_coderunner).
Error at Create a CodeRunner Question
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