Coursepress update not working

After upgrading I get this error:

Warning: call_user_func_array() expects parameter 1 to be a valid callback, class 'CoursePress_Core' not found in /home/kstudiof/public_html/VESTORPRO/wp-includes/class-wp-hook.php on line 298

Warning: call_user_func_array() expects parameter 1 to be a valid callback, class 'CoursePressPro_Core' not found in /home/kstudiof/public_html/VESTORPRO/wp-includes/class-wp-hook.php on line 298

Warning: call_user_func_array() expects parameter 1 to be a valid callback, class 'CoursePressPro_Wpmudev' not found in /home/kstudiof/public_html/VESTORPRO/wp-includes/class-wp-hook.php on line 298

Fatal error: Class 'CoursePress_Upgrade' not found in /home/kstudiof/public_html/VESTORPRO/wp-content/plugins/coursepress/coursepress.php on line 179