A regular override gives you permission to register for a seat in a class as long as a seat is available in that class. It does not save a seat for you. A regular override is generally given to prevent or resolve a registration error message stating that you don’t have the prerequisites for a class.
A closed class override actually saves a seat for you in a class, but you must still register for that seat. A closed class override is generally given after a class fills, if and when more seats have been added to the class or someone has dropped the class. If a student is given a closed class override but does not exercise it by registering within a reasonable period of time, sometimes the override is removed, giving others the chance to register for that class. Before the override is removed, however, the MBA office makes every effort to contact the recipient of the override to encourage them to register.