AC313u modem won't connect on recently upgraded windows 10 system

I installed AT&T AllAccess and then plugged the modem into a USB port. This is on a system recently upgraded from Win7 to Win10 Home. The AC313u has worked fine with XP, Vista, and Win7 just fine. However, the Win10 upgrade doesn't connect to the modem. Would I need perhaps a driver or new firmware, etc., and if so how when I can't connect to the internet? Thanks for any ideas. Buck