On a display unit of a client terminal, a to-be-uploaded folder and a to-be-uploaded file, a display area associated with computer program that provides uploading function, and the like are displayed. When a user operates a mouse and the like such that a pointer is placed on the to-be-uploaded file and performs a drag-and-drop operation into the display area, the to-be-uploaded file is uploaded to a file management server via a network.