Method and apparatus for recovering aborted file (or data) transmission

A system for transmitting files includes a transmitting terminal and receiving terminal. After a file transmission has aborted, the receiving terminal generates a size and checksum for the portion of the file received by the receiving terminal. The transmitting terminal generates the checksum based on the corresponding portion of the file stored in the transmitting terminal in reference to the size. The transmitting terminal re-starts the file transmission process if the checksum generated at the receiving terminal does not match that generated at the transmitting terminal. The transmitting terminal transmits the rest of the file that has not received by the receiving terminal if the checksum generated at the receiving terminal matches that generated at the transmitting terminal.