Recently my Xperia L running Android 4.2.2 started restarting every 30 seconds following a factory reset.

I have rooted my phone using the iroot app and I reset it. I still have the kinguser app installed, I cannot uninstall it. Every time it boots, after 20-30 seconds it restarts. I'm using a stock ROM and I've never installed a custom one.

How can I stop my phone from restarting?

I've did a Google search on rooting your phone and have realized that all the available methods suggest the user to first unlock the bootloader and later root it.

Maybe Sony has put some barrier to prevent these kind of situations or maybe this is a failed factory reset. Hence, I suggest you reboot the phone into fastboot mode and do a factory reset.


  1. Download the appropriate USB drivers for your device.
  2. Download the slim version of ADB and Fastboot. You can find this in
  3. Install the USB drivers for your device.
  4. Now, search Google on HOW TO BOOT your device in fastboot mode or bootloader mode. Note: There is a way to boot the device into fastboot mode directly but since your phone reboots every 25-30 seconds, this cannot be possible.
  5. After you reboot to fastboot mode, goto Start > Run and type cmd
  6. Extract the previously downloaded adb and fastboot and type cd c:\path\to\adb\directory
  7. Type fastboot devices. Note: fastboot and adb require Administrator privileges to work in Windows 8 or later.
  8. Now if you can see a device besides a blank input, then you have installed the USB drivers correctly.
  9. Now, type fastboot erase userdata and fastboot erase cache.
  10. Now reboot by typing fastboot reboot and wait.

With a little luck, your device might boot.

I have been in the same situation. I rooted my phone Sony Xperia and it kept restarting. I reset it via the recovery menu and Kinguser was still there and I finally got rid of it. Do these steps and you will have your phone working again:

  1. Go to Google
  2. Search for Kingoroot
  3. Install Kingoroot for Android
  4. Click "root" at the bottom
  5. Your phone will reboot and Kinguser is gone
  6. Android 4.2.2 is working again

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