On computers old or new, MS-DOS INT 24 error means a critical error has occurred, probably failure to write to disk. It is usually followed by the prompt (ABORT, RETRY, IGNORE). Possible causes: Hardware failure (hard disk drive or controller), hard disk cable faulty or loose, hard disk incorrectly partitioned. Other possibilty: ancient (reported 1992) MS-DOS virus ("Green Joker") has infested every .com file in MS-DOS boot media. This is less likely given that the Windows installer also fails.
