A driver management apparatus is installed in a system including an image forming apparatus and plural information processing apparatuses. The driver management apparatus sends the information processing apparatus a driver for the image forming apparatus with a first key incorporated. The driver is so set that printing processing conditions whose designation with the information processing apparatus is prohibited cannot be designated. Further, the driver management apparatus sends the first key to the image forming apparatus. The information processing apparatus uses the driver sent by the driver management apparatus to generate print data and encrypts the generated print data using the first key incorporated into the driver, and sends the encrypted print data to the image forming apparatus. The image forming apparatus decodes the print data received from the information processing apparatus using a second key of the information processing apparatus and performs a printing process using the decoded print data.