As these machines get old, the little radios can drift and we are also seeing another issue where the RF "soup" is getting thicker. I guess that would only make sense to electronic designers but see if you can use a USB cable to avoid replacing this keyboard.
My wife's HP touch smart, IQ500 Series, Windows Vista's key board becomes unresponsive. It doesn't do it all the time but it does it a lot. I have tried to refresh the page, that doesn't do anything. The batteries are new, I changed them and put other new ones in and still nothing. In ten minutes or so the keyboard will be OK. Oh yes, this is a wireless keyboard, the mouse works good all the time. Does anyone have any ideas as to what is happening.