Unable to Delete a Grade Center Column
Issue: Instructor does not have the option to delete a a column in the grade center.
Cause: The only time a grade center column ever has the option to delete it is if the column was created manually (Create Column.) If you need to delete a column that was automatically created in the grade center while creating an Assignment, Discussion Board, Test, etc. then you must first delete the active Assignment, Test, Discussion Board, etc. within the course. If the column is still connected to an active assessment the option to delete is not available.
There is a rare instance where a column cannot be deleted even if it was once connected to an active assessment and is no longer. This could happen during a course copy or when the instructor goes to delete the Discussion Board and they are give a red banner warning that says "You can choose to delete the grade center columns at the time you delete the discussion board." Then there is another warning that says "If you choose to remove the grade center columns the data will be lost."
This is usually the time when most instructors choose no because they are afraid that it will cause data loss.
Resolution: To avoid this issue, select yes for this option. If you do not and run into this issue the best thing to do is to open up a support ticket and ask that we remove them for you.