A message server for transferring a file by using hypertext transfer protocol (HTTP) during a chatting session established by another protocol, includes: a server transceiver unit configured to transmit and receive data; and a server control unit configured to provide a chatting service by establishing the chatting session between a transmitting terminal device and a receiving terminal device through the server transceiver unit, and transmit file link information to the receiving terminal device through the server transceiver unit when the file link information is received from the transmitting terminal device through the server transceiver unit, wherein the file link information is associated with a file uploaded using HTTP to a content server by the transmitting terminal device.