iTunes won't recognize iPhone 5c when it is connected to computer

For some reason my iTunes app stopped recognizing my iPhone when I tried to sync photos. I previously have synced many times. The phone icon does not appear in the little place where it should be at the upper left corner of the iTunes screen, and I cannot even get to the series of screens I need to sync photos (and anything else).
Help, someone!

Have you updated your 5c to iOS 10? If so, you will need to update iTunes to version 12.5.3 which contains the necessary drivers for iOS 10.

Good point Kevin. Lots of folks straight away update their iPhone to the latest version of iOS without realizing that iTunes also will need to be updated so that syncing can continue as before. However, some folks may not be able to update to the latest iTunes if their version of OS X is too old.

That's true. My Windows PC runs Vista, which can no longer be updated.

iTunes 12.5.3 requires OS X 10.9.5 (Mavericks) or later.