I have run into a peculiar problem, which may or may not be simply explained. My original 10-year old Apple A1243 (sold with my PPC iMac) wired keyboard seems to have failed, so I purchased a second-hand Apple A1243 keyboard from eBay. It also doesn’t work, so I automatically assumed that it is broken, and that I'd been sold a broken one. But, seeing as my original one also doesn’t work, I thought that it might actually be my computer as that it seems reasonable to think that its fantastically unlikely that two different keyboards from two totally different sources both don’t work. The seller, whist assuring me that it was fine when he sent the new-old one to me, has kindly said that I can return the keyboard to him if I need to. I have also tested both keyboards out on my laptop, and again neither of them work so to be trebley sure, I asked my friend to try them on her own iMac. She tells me that they also both don't work for her either. So now I'm foxed; I have done all the likely things, like removed all other USB devices and run Disc Utility. Maybe they both really don’t work, after all, and Apple A1243's have something of a shelf-life. The fact that both keyboards don't work on either of our computers leads me to believe that they both indeed don't work. Many thanks if you have any suggestions.