Setting system, image processing device, remote control method, and remote control program

An image processing device includes: a hardware processor configured to: execute a process according to a received remote operation in response to reception of the remote operation from a master device registered in advance among a plurality of mobile information devices; confirm to a duplicate login device other than an own device among the plurality of image processing devices that the duplicate login device is remotely operated by the master device in a case where a remote operation of instructing connection with a sub device different from the master device is received from the master device; and execute a process according to a remote operation received from the sub device in a case where it is confirmed by a confirmation unit that the duplicate login device is remotely operated by the master device.