How do I fix su binary occupied? 

Install SuperSU 2.65 and update binary, then reboot, and update from Play Store, then update binary again (using “normal” option).

How do I fix SuperSU binary occupied?

Install SuperSU 2.65 and update binary, then reboot, and update from Play Store, then update binary again (using “normal” option).

What is su binary in Android?

Su binary are Superuser.This binary are installed when you try to root your phone using apps like kinguser or via fastboot in Android. These files are necessary so that one can root there phone and becomes the superuser.