1. An image forming apparatus capable of connecting a removable storage device that stores operation data controlling an operation of the image forming apparatus, the apparatus comprising: a determination unit configured to determine, in a case that a shutdown instruction of the image forming apparatus is received from a user, whether or not it is necessary to execute an operation using the operation data stored in the removable storage device; a restarting unit configured to save the operation data stored in the removable storage device into an incorporated non-volatile storage unit and to shut down the image forming apparatus, and then restart the image forming apparatus, in a case that it is determined by the determination unit that it is necessary to execute an operation using the operation data; and a control unit configured to control so that, after a restart is performed by the restarting unit, an operation using the operation data that has been stored in the incorporated non-volatile storage unit is executed.