You may not get this USB debugging authorisation prompt.This is where things get a little flaky due to my PC having been used before for rooting.So I went into network settings and changed my mobile network to 3G and also tried 2G/GSM. I switched the phone back to 4G and it drops to 1 bar.So the solution seems to be to switch the phone to 3G or GSM when I’m at home as I don’t really need 4G because the phone is connected to my wi-fi for data.Go back up to the settings menu and the “Developer options” menu should now be available. If your PC can see the phone at this point, a message should pop up on the phone asking you to authorise your PC for USB debugging.It will show an RSA key, so just click “OK” to allow it.
I noticed I only had 1 bar of signal even though I would normally have a full 5 bar signal, the mast is literally just down the road.So, let me know in the comments if Kingoroot can talk to your phone at this point or not and I will update this post accordingly.If it can’t, then you may need to try installing the Samsung USB drivers.On my PC, when I use ADB I get the following message before authorising debugging: Don’t worry if you don’t understand all this ADB stuff, you don’t need it. It takes a little time to run, probably 5-10 minutes whilst it analyses the phone for a rooting method.Eventually it will show a screen saying it is ready to root and give you the usual warning about it possibly bricking your device.Go to device manager on your PC (you can find it in Computer- If your device manager doesn’t show this, it’s possible Kingoroot may still work, but I couldn’t say.