For those trying to connect their android phone in adb with no luck and have tried every USB configuration (MTP, PTP, RNDIS). It is worthing noting that in my case with my Nexus 5X on Windows 7 I successfully connected the phone to adb only by choosing the Charging USB Configuration. With any other configuration (MTP, PTP, ...) it doesn't work.
USB Driver: Google USB Driver v11
ADB Version: Android Debug Bridge version 1.0.39