Hello - Thank you anyone verrrry much for any helpful advice you can give. I have had a MacOSX for about 4 years, along with the keyboard and mouse that came with it. There had been no problems until last week. It seems I may have caused a problem when I started moving the position of the keyboard experimentally. I had seen a website that showed how a man cured his carpal tunnel by placing his keyboard at a 90 degree angle (will give anyone the website, with pictures, if you want it) from the desk so that he could use it while standing - thus putting his wrists, and in fact his entire arms, in a straight line down from his body. A day or two after I tried placing my keyboard in that position, just experimentally, it started to malfunction. Sometimes when I turned on the computer it would works, most times it was dead, as was the mouse connected to it. I went out and bought a new Media Pro wireless keyboard and mouse, and they would not work either (possibly due to something I wasn't doing right?). Then I bought a Media Pro that was wired to plug in, but it also would not work. The temporary solution I have found is that, once the keyboard came back to life after several times of turning the computer on and off, is to not turn the computer off anymore, but just leave it on day and night. What I am hoping someone will be able to help me decide is - do I have a problem with the computer itself, or just with the keyboard? A salesperson at Staples said I probably bent the wire on the keyboard when I was trying different positions, and hurt the inner wiring. However, since the non Mac, new, keyboards did not work either, I don't know - but hope - that he is right. Are some keyboards not Mac compatible, though they say that they are on the box? Would getting a new Mac keyboard make a difference? In the meantime, everything else is working fine, including a Painter Classic program and it's electronic stylus. Thank you so much for any help.