Back up iphone to computer tab is grayed

Trying to backup my "i"phone iOS 9.3.2

I see "i" phone on my computer (internal storage) ; I can open pictures

i tunes does not recognize i phone device tab (all backup, sync, restored, tabs are grayed)

connected by usb cable

latest update for itunes is completed

Recommendation to solve backup phone issues, last update was April 13