An image forming apparatus includes a communication interface, a printer, and a processing circuit. The communication interface is configured to receive a message regarding a print job and including first user information of a first domain. The processing circuit includes a processor caused to: store second user regarding users who can perform printing and belonging to a second domain different from the first domain, and link information regarding linking the first user information and the second user information; extract the first user information from the message based on a determination that the first user information is linked to the second user information in the link information; print an image based on the printing job using the printer; and based on a determination that the first user information is not linked to the second user information in the link information, generate a registration URL for registering the link information.