Int 21 Fn D5AA - Virus - "diamond-a", "diamond-b" - Installation Check [v] AX = D5AAh Return: AX = 2A55h if "Diamond-A" resident AX = 2A03h if "Diamond-B"-family virus resident See Also: AX=D000h,AH=D5h"VIRUS",AX=D5AAh/BP=DEAAh