How To Create Undeletable And Unrenamable Folders ?

Go to Start and then Click on Run Type cmd & hit enter (To open Command Prompt ). 
Remember you cannot create Undeletable & unrenamable folder in your root directory (i.e. where the windows is installed) That means you can't make this kind of folder in C: drive if you installed windows on C: Type D: or E: and hit enter Type md con\ and hit enter (md - make directory) 
You may use other words such as aux, lpt1, lpt2, lpt3 up to lpt9 instead of con in above step. Open that directory, you will see the folder created of name con.
 Try to delete that folder or rename that folder windows will show the error message.

How to delete that folder ?

It is not possible to delete that folder manually but you can delete this folder by another way mentioned below.

1. Open Command Prompt
2. Type D: ( if u created this type of folder in D: drive) & hit enter
3. Type rd con\ (rd - remove directory)
4. Open that directory and the folder will not appear because it is removed.

Setting Video As Desktop Wallpaper...!!!!

How to set video as desktop wallpaper ?

   1. Open VLC Media Player. If you don't have it download it frome Here.
   2. Then Go to Tools > Preference Or press CTRL + P and Selecet Video from left panel
   3. Then Choose DirectX video output from output dropdown list
      as shown in below image .

   4. Save the changes ans restart VLC Media Player.
   5. Play any video you would like to set as your desktop wallpaper.
   6. Then click on Video and select DirectX Wallpaper from the dropdown list as show in below image.

   7. Now Minimize vlc player and you will see your video running on your desktop as wallpaper.
   8. If you want your default wallpaper back then uncheck DirectX Wallpaper from video dropdown list.
   9. Hope you like this simple trick share your thought about this trick in comment section.