  Phone must be rooted!
If the software can't root the phone automatically, 
then you must root your device manually.
1. Power on the phone.
2. Tap 7 times on "Build number" in "Settings"-"About phone" to enable "Developer options",
   go to "Settings"-"Developer options" and enable "USB debugging".
3. To use "Auto backup/restore QCN" function (recommended):
   Type *#0808# and select "DM+MODEM+ADB".
   Type *#9090# and select "DM/DUN over HSIC".
   Or you can disable this function and use ADB only.
4. Connect the phone to PC with USB cable, install drivers if needed.
5. Select diagnostic port in port settings if "Auto backup/restore QCN" is not skipped.
6. Select device in ADB settings.
7. Press "Unlock" button for direct unlock.