What if the same happens in poser 7 and reinstallation doesn't help? And there is no libraryPrefs.xml. Problem occured after installing V4 stuff. Should I install Poser 7 in a different folder and move the libraries into this new folder, untill I get this message again, so I can see, what causes that problem? I have lots of stuff in there, would take me forever, so I would be very thankful for any other help, before I have to go this step.