PASSWORD YOUR FILES WITHOUT ANY SOFTWARE:

First create a compressed (zip) folder and then open it. paste the files 
here that you want to protect with password. Now do right click 
anywhere in that folder and select "ADD A PASSWORD" option.


A box will appear. Enter your desired password in it and press OK button..
DONE!!

Now your files are password protected and will require password to open..


HOW TO CREATE A COMPRESSED (ZIP) Folder??

do right click and go to New>Compressed (zip) folder. Done!!