Hello Mike, a common issue is to have a hub in between.
It works often but there is no guarantee to it.
I assume you've tried different USB ports too.
Unplug all other synth...
Finally, maybe this will help, try a USB tool I am using for different USB issues for years:
http://www.nirsoft.net/utils/usb_devices_view.html
Windows is quite bad in managing USBs - espessially if unused drivers are in the way.
This tool shows old drivers too, and you can uninstall those.
Good luck,
R.