I bought this product for its supposed qualities, in fact I have several problems: many key shortcuts do not work: F1, F3, F4, F9, F10, F11, and sound adjustment buttons, and the calculator button. Furthermore the setting of various timing functions of the keyboard illumination works randomly and unsatisfactory. I sought advice from Logitech that told me that this keyboard was probably corrupted and had to change it (which was not a problem with Amazon). Unfortunately the new keyboard has the same defects. I concluded that these keyboards do not work, or poorly, with Windows XP, I tried to show these two keyboards with another computer too, Window XP, even negative results. It is obvious that if I had known this I would have chosen a different keyboard. Other fault load the keyboard lasts only three days, max, unlike the specifications. Only positive criteria: aesthetics, silence keys and ergonomics.