The "sleep" button on my computer keyboard won't effect the hibernate function on my Windows XP Home Edition computer. It worked well until several months ago and then, all of a sudden, it stopped functioning. I can get it to hibernate by using Start-Turn Off Computer-Stand-By, but the "Sleep Button" does not work. I did some Internet research and one site indicated that it might be a driver problem. Does anyone have any experience with this or know of a solution? Thanks in advance.