Solved 100% working Lenovo Adjusting Screen Brightness in Windows

Follow these steps :

1. slide any right corner and click on 'Search'.

2. Write "Regedit".

3. Press F3 in regedit to open the search dialog box (or select "Edit" menu).

4. Write the key and give FeatureTestControl "Find Next".

5. Once found FeatureTestControl right click, select "Modify

6. Replace the original value by: FFFF

7. Restart and problem solved

Work 100 %!

Working with win 10