Eu tenho um teclado Logitech quase idêntico a este e tive o mesmo problema. Aqui está o que Logitech diz :
When you are using a corded iTouch keyboard, the F-Lock function will always be on when you boot your computer. There is no way to change how this feature works; however, you can work around this feature using the Transparent Pass-Through key assignment. By programming a function key to Transparent Pass-Through, the Enhanced function is bypassed and the function keys will perform their normal purpose even though the F-lock key is still on.
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If you are using a cordless keyboard, the F-Lock feature will be in whatever state it was prior to shutting down Windows. This means if the F-Lock feature was on when you shut down Windows, it will be on when you reboot and if it was off when you shut down, it will be off when you reboot.
Felizmente, o meu é sem fio.