USB debugging is turned off permenantly / grayed out I have recently installed euphoria lollipop custom ROM on my sony xperia l c2105. Now am facing lots of difficulties over it. My phone inbuilt memory is tollay ruined. Now my navigation bar icons also stops working I can't able to switch between apps, minimize app, can't go back so I decided to roll back to generic os. But I can't turn on my USB debugging. It shows in charge mode and USB debugging is grayed out .This post helps you to turn your USB debugging.I have surfed in Google and found the results. Steps to turn on USB debugging when it is permanently grayed out. Step 1: connect your mobile to computer via data cable. Step 2: drag your notification panel and click change USB mode. Step 3: switch to MTP from charge only Step 4: now go to settings -> developer options. Now you can turn your USB debbuging on.