Print system and print method

A print system comprising:

• a client terminal;
• a printer;
• and
• a server connectable to the client terminal and the printer over a network, wherein
• the client terminal comprises:
• a first communication interface;
• a scanner;
• and
• a first processor configured to control the first communication interface to transmit a print job to the server,
• the server comprises:
• a second communication interface;
• and
• a second processor configured to, in response to reception of the print job, obtain an unlock code associated with the printer and control the second communication interface to transmit the unlock code to the printer, and
• the printer operable in an unlocked state and a locked state, and comprises:
• a display;
• a print engine, printing of which is enabled during in the unlocked state and disabled during the locked state;
• and
• a third processor configured to, in response to reception of the unlock code, control the display to display an optically-readable code that represents the unlock code and represents a sever identifier of the server, wherein
• the first processor of the client terminal is further configured to control the first communication interface to transmit a first request including the unlock code to the server identified with the sever identifier in response to scanning of the optically-readable code by the scanner, and
• the second processor of the server is further configured to perform verification of the unlock code included in the first request with the unlock code associated with the printer, and after the verification control the second communication interface to transmit a second request to the printer, thereby causing the printer to turn into the unlocked state, and transmit the print job to the printer, thereby causing the print engine to perform printing based on the print job.