Need original files for 'Matsushita BD- CMD UJ-120B' or 'Optiarc BD ROM BC-5500 A. They are both shown on Sony Vaio site with upgrades, but the original files are gone or corrupt in registry. I have VGN-AR825E model which came with Vista But I upgraded to Win 7, and this has been the main problem. It doesn;t even show a DVD drive on 'My Computer'