If u update losdor k518ise get error,you need to Brush Machine,below is the steps:
How to do Brush Machine for Lonsdor k518ise ?
1. Download Lonsdor k518ise Brush Machine File and unzip the attached file.
2. Install and then open the app
3. Use a USB cable to connect your K518ISE to a computer.
4. ① Click the button in red first.
② Click the button in black next.
③ Find the file 
and click it (marked in
red, step 1).
④ Then click the button marked in black (step 2).
5. Hold on the power key and you will see interface below. Click the button marked in red. And immediately hold on the volume+ key until you see a progress bar in the computer.
6. Two windows will pop up, just click YES.
7. Update firmware successfully. Pull out the USB cable and wait the device to automatically repair.
8. Don’t touch the device. You will see a white screen and there are two buttons (set up WIFI and update).
9. Set up WIFI and then update. The problem will be solved after updating