Abstract: A storage device, having the function of coping with a computer virus which has the ability to prevent infection with a computer virus and properly deal with infection with a computer virus, comprises: an infection management table used to manage files stored on a disk to see if the files are infected with viruses; a table registering unit for receiving a result of detection from a virus checker for detecting if a file stored on a disk is infected with a virus, and for registering the result in the infection management table; a judging unit that when a use request is made externally for a file stored on the disk, references the infection management table so as to judge if the file is infected with a virus; and a prohibiting unit that when the judging unit judges that a file is infected with a virus, prohibits the use of the file.