I have been using two displays for several years with various releases of Windows. I have been using my two displays under Win 10 for several months. Recently, I had to re-build my Windows10 system (now, Pro build 10240) and suddenly my two displays no longer work as before. They are recognized as two displays by the system and I can use either one as a single display, but extending my desktop across BOTH doesn't work--just blank/black screens on both displays with the task bar displayed across the bottom of whichever display I have designated as the primary display. I can also duplicate the desktop across BOTH displays, but cannot extend the desktop across both displays.
No error messages, no desktop photos on either display. The system seems to be working fine otherwise, all apps seem to be working o.k. I have refreshed all display device drivers and nothing seems to work I am at a loss as to what to do next. Any suggestions?
