I have done a clean install of Windows 10 1709. System, including on board USB, works fine until I plug into the motherboard connectors with external USB devices - card reader, front side usb ports. Then when I go to windows, Cortana box and Start menu and task bar are inoperable. When I shut down, I get the Taskhost is stopping..... message.
Have done the clean install several times and also did System File Checker.