Students cannot access course units - receive error message

When I access a unit with an account with student access, I receive a blank page with the following error message:

Units
Notifications
Discussions
Workbook
Course Details

Warning: Creating default object from empty value in /home/ashebibletrainin/public_html/wp-content/plugins/coursepress/includes/classes/class.shortcodes.php on line 3017

I've found this error on your forum without an actual solution.

Units were working fine before the latest update.