You all may know how to hide the folder icon in Nokia S40 series by the folder extension .otb. But exactly, that was not folder hiding, but just a its icon hiding.
Now, i have a new trick to hide the entire folder in Nokia S40 series.
Follow the steps to hide the folder in your mobile phone:

Make a folder with any name but , the name should end with the extension ‘.jad’.
Move all the files and folders that you want to hide to this folder.
Then, make another folder with the same name , but it should end with the format ‘.jar’.
when you create that folder with the extension .jar the first folder with the extension .jad will disappear from the phone.

That’s all you want to hide a folder.

To unhide the folder just rename ore delete the .jar folder
Check it out, and Comment this post.