When a student clicks 'Grades', the message 'Can not view gradse.' appears and the gradebook is not accessible.

(The image below is the Student screen.)

If you want to disclose the gradebook to students, you should change the setting of 'Show gradebook to students'.

(1) Click the 'Course administration > Edit settings' on the left side of Course page.

(2) Change 'Show gradebook to students' to 'Yes'.

(3) Click the [Save] button.