Thanks for the speedy reply... I have a microsoft optical mouse and keyboard and at the moment I haven't connected my scanner or printer... This problem started before I had my LCD monitor, I was still using my old mouse, keyboard and standard monitor.. except then I didn't get the error message, just a black screen! I think maybe the problem is between Poser and my graphic card!! According to my manual the 'input not supported' message appears when the computer is trying to get the monitor to do something it can't! I can't understand why this only happens to Poser 4 and 5 and why sometimes I can work perfectly well for hours!