A learner is receiving a 'You are not authorized to access this page' message when trying to access a course object.
Is there grade, date, or condition based access set on any of the course objects?
Is the content in the next course object in workflow shared across multiple courses? This can be checked with the course content usage report. If content is shared, ensure the content is either in private objects across all shared courses, or public.
Is there content referenced for each course object?
Is the content referenced in the object published?
Was a course object recently deleted?
Is the course object set to visible in the course outline?
Is there a payment object on the course? Was it added or made required recently? If so, learners could be blocked if they had enrolled before the payment object was added/made required. The payment object may be manually completed by editing the enrollment and marking the Payment object as completed.
If the learner navigated to the course object via a direct link was the link that the user was given a link that enrolled users have access to? For providing learners with direct links to course objects see Deeplinks to Objects.