$groups = groups_get_all_groups($course->id, $USER->id);
if (is_array($groups) && count($groups) > 0) {
$groups = array_keys($groups);
+ } else if (groups_get_activity_groupmode($cm, $course) != NOGROUPS) {
+ // If the user is not in a group, and the quiz is set to group mode,
+ // then set $gropus to a non-existant id so that only users with
+ // 'moodle/site:accessallgroups' get notified.
+ $groups = -1;
} else {
$groups = '';
}