From: https://discussions.apple.com/thread/6610010?tstart=0

Has to do with device driver


SirBenn21
Oct 21, 2014 12:28 AM 
in response to sincerelynaly
Solved
Okay
 
I got it working. You have to uninstall all three associated programs and then reinstall iTunes 12
 
This worked for me

Note Drivers for USB of iPhone:https://discussions.apple.com/thread/7508030?start=30&tstart=0

Browse to C:\Program Files\Common Files\Apple\Mobile Device Support\Drivers or
                C:\Program Files (x86)\Common Files\Apple\Mobile Device Support\Drivers
                
                turingtest2
Apr 5, 2016 11:48 AM 
in response to Demi Vera
Apologies in advance for a little repetition, but some things may be new to some readers, even if they are things you have tried already.
 
Try the following:
 
Open Control Panel > Device Manager
Plug in your device
Locate Universal Serial Bus Controllers > Apple Mobile Device USB Driver. 
It is also possible the device may show under Imaging Devices, Portable Devices or Other Devices or as an MTB USB Device.
Right-click and select Update Driver Software...
Click Browse my computer for driver software
Browse to C:\Program Files\Common Files\Apple\Mobile Device Support\Drivers or
                C:\Program Files (x86)\Common Files\Apple\Mobile Device Support\Drivers
Click Let me pick from a list of device drivers on my computer
Click Apple Mobile Device USB Driver
Click Next, then Close and exit Device Manager