MARINE PROPULSION DEVICE INFORMATION TRANSMITTING AND RECEIVING SYSTEM AND MARINE PROPULSION DEVICE INFORMATION TRANSMITTING AND RECEIVING METHOD

A marine propulsion device information transmitting and receiving system includes a watercraft and a server. The watercraft includes an engine and a controller to control the engine. The controller encrypts an operating time of the engine and data related to the engine with an encryption key associated with information unique to the engine. The watercraft includes a communicator to transmit the information unique to the engine, the encrypted operating time of the engine, and the encrypted data related to the engine to the server. The server decrypts the encrypted operating time of the engine and the encrypted data related to the engine with the encryption key associated with the information unique to the engine, and determines whether or not the decrypted data related to the engine are genuine based on the decrypted operating time of the engine.