Schools may restrict enrollment in particular courses, so students should review the course descriptions or view course offerings  on the Registrar website, paying particular attention to class notes.  For instance, some courses, such as upper-division courses in business, are open only to students officially enrolled in certain schools. Other courses may be restricted to students with sophomore, junior, senior, or graduate student status. Finally, some courses require a student to have completed one or more courses prior to enrollment (known as "prerequisites"). Otherwise ineligible students who believe their personal preparation overrides the restrictions of a class may seek the department's or instructor's permission to enroll in  the class.

On occasion, students have a hold placed on their enrollment. When this occurs, they cannot register for courses because they have failed to meet some requirement of the university or school and cannot proceed until the problem is resolved. Problems that result in a hold include academic probation or dismissal or failure to pay tuition or other fees. Students with unpaid library fines, outstanding parking tickets, or a disciplinary problem also may be placed on hold. Students can review their status on OneStart, and if they find they have such a hold, they should contact the office(s) listed on that hold to resolve the problem.