An IFAX on a transmitting end gains access to an ISP on the transmitting end by dialup. The IFAX on the transmitting end transmits mail transmission notice to an IFAX on a receiving end via a PSTN after transmitting e-mail to the ISP on the transmitting end. Thereafter, the IFAX on the receiving end gains access to an ISP on the receiving end by dialup in accordance with mail transmission notice and receives e-mail stored in its own postbox. The mail transmission notice is performed using a facsimile communication protocol. The mail transmission notice includes at least one of transmission finished notice information, sent data information, and receiving information. This eliminates the unavailing mail check connection and reduces access charge at a dialup IFAX of the Internet facsimile.