32 in association with the user information (step S502).

Thereafter, the person in charge of sales accesses the head management page from the sales company terminal 20 and performs operation for enabling self-repair of the registered printer 60 (step S103). The server control unit 11 receives the operation, adds information indicating that the self-repair is enabled to the printer information and updates the printer information (step S503).

When the self-repair is enabled, the user is capable of purchasing the printing head 66 for replacement. The user accesses the head management page from the user terminal 50 and requests purchase of the printing head 66 for replacement (step S404). It is desirable that the purchase is performed not after a failure of the printing head 66 but before the failure.

When receiving the purchase request from the user, the server control unit 11 notifies the sales company terminal 20 that the purchase request is received (step S504). When receiving the notification, the person in charge of sales instructs, from the sales company terminal 20, the person in charge of distribution terminal 30 to deliver the printing head 66 to the user (step S104).

The person in charge of distribution receives the instruction and selects one printing head 66 to be delivered out of the stocks of the printing heads 66. In the delivery base, the printing heads 66 are stored in individual packing boxes. The same QR codes as QR codes attached to the printing heads 66, that is, QR codes in which head IDs of the stored printing heads 66 are written are attached to the surfaces of the individual packing boxes. When the person in charge of distribution images, with the imaging unit 26 of the person in charge of distribution terminal 30, a QR code attached to an individual packing box of the selected printing head 66 in a state in which the person in charge of distribution accesses the head management page from the person in charge of distribution terminal 30, the person in charge of distribution terminal 30 reads a head ID from a captured image of the QR code and transmits the head ID to the server 10 (step S201).

The identification-information acquiring unit 14 of the server 10 acquires the transmitted head ID and registers the head ID in the delivery history of the head management database 32 in association with the user information of the user who has requested the purchase (step S505). The acquisition and the registration of the head ID are performed before the printing head 66 is delivered. The head ID registered in step S505 can be referred to later as a history of the instruction of the delivery. In the head management database 32, since the user information includes the address of the delivery destination, an address of a delivery destination to which the printing head 66 should be delivered is associated with the head ID registered in the delivery history. Since the printer information is associated with the user information, a printer ID included in the printer information corresponding to the user information is associated with the head ID registered in the delivery history. That is, the printer 60 to which the printing head 66 to be delivered should be attached is determined by the registration. In other words, a combination of the printing head 66 and the printer 60 is determined. Thereafter, the person in charge of distribution makes arrangements for delivery of the printing head 66 with the delivery company (step S202).

The person in charge of delivery receives, from the distribution base, the printing head 66 to be delivered and delivers the printing head 66 to the delivery destination (step S301). After the printing head 66 arrives at the delivery destination, before sending the printing head 66 to the user, the person in charge of delivery images, with the imaging unit 26 of the person in charge of delivery terminal 40, the QR code of the individual packing box of the printing head 66 in a state in which the person in charge of delivery accesses the head management page from the person in charge of delivery terminal 40. When the imaging is performed, the person in charge of delivery terminal 40 reads the head ID from a captured image of the QR code and transmits the head ID to the server 10 (step S302). The identification-information acquiring unit 14 of the server 10 acquires the transmitted head ID and registers the head ID in the delivery history of the head management database 32 in association with the user information of the user who has requested the purchase (step S506).

Further, in a state in which the person in charge of delivery accesses the head management page from the person in charge of delivery terminal 40, the person in charge of delivery inputs the address of the delivery destination as information concerning the delivery destination to which the printing head 66 has been actually delivered (step S303). The delivery-result acquiring unit 15 of the server 10 acquires the input address of the delivery destination and registers the address of the delivery destination in the delivery history of the head management database 32 in association with the user information of the user who has requested the purchase (step S507). The head ID and the address of the delivery destination registered in steps S506 and S507 can be referred to later as a history of completion of the delivery.

Thereafter, the determining unit 17 of the server 10 determines, based on the delivery history, whether the printing head 66 has been delivered to a correct delivery destination (step S508). Specifically, the determining unit 17 determines whether the address of the delivery destination input by the person in charge of delivery, that is, the address of the delivery destination acquired by the delivery-result acquiring unit 15 and the address of the delivery destination included in the user information, that is, the address of the delivery destination associated with the head ID of the delivered printing head 66 coincide. When the addresses of the delivery destinations do not coincide (NO in step S508), the determining unit 17 determines that an abnormality concerning the delivery, that is wrong delivery has occurred. The notifying unit 18 of the server 10 notifies the sales company terminal 20 that the wrong delivery has occurred (step S509). When receiving the notification, the person in charge of sales takes measures against the wrong delivery, for example, makes contact with the person in charge of distribution or the person in charge of delivery and causes the person in charge of distribution or the person in charge of delivery to deliver the printing head 66 again (step S105). On the other hand, when the printing head 66 is delivered to a correct delivery destination (YES in step S508), the server control unit 11 executes processing in step S510 and subsequent steps.

When the printing head 66 is delivered, the user keeps the delivered printing head 66 until the printing head 66 attached to the printer 60 at that point in time breaks down (step S405). The user determines, based on a printing result and the like, whether the printing head 66 is out of order while using the printer 60 everyday (step S406