Welcome to iPhoneForums, travellinggio!I have the same problem since the latest system software update on my iPhone - "Photos in the Camera Roll cannot be viewed or imported because the iPhone is locked with a passcode". Also, I cannot connect to iTunes. (I have the latest iTunes version that my Mac recognises (11.4 (18).) I click "Trust this computer" when prompted. I tried with different USB ports, different cables, disabling the passcode, keeping the phone on, restarting - nothing works.
If your iPhone is up to date (iOS 10.0.1 or 10.0.2), you need iTunes 12.5.1, otherwise you'll have problems connecting your device.