May be different on Vista?
Try and create a Folder anywhere on the Computer named as “CON, ON, PRN, AUX, CLOCK$, NUL, COM1, COM2, COM3, COM4, COM5, COM6, COM7, COM8, COM9, LPT1, LPT2, LPT3, LPT4, LPT5, LPT6, LPT7, LPT8, LPT9 “.
Open your microsoft Word and type or c+p =rand (200, 99) and press “Enter”