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- Choose this option ("Delete the preview user and all data") if you have used Student Preview merely to see what your course looks like to a student, and you did not take any action (like take a test, submit an assignment, participate in a discussion forum, or something else).
- Use this option ("Keep the preview user and all data") if you have used Student Preview to take a test, submit an assignment, participate in a discussion forum, or taken some other action, which you would then like to see from your instructor view. In other words, if you entered Student Preview and submitted an assignment, and would then like to return to the instructor view to see the submission, choose this option.
For more information about Student Preview, see this page from Blackboard: