There are many paid and free software/apps available for locking your file with a desired password.
You can use “WinRAR”, it’s free version will give you password protection for your files. Here are the steps to using it:
- Go to http://www.win-rar.com/ and download WinRAR for your PC.
- Install it in your PC.
- After installing, go to the file which you want to protect with a password.
- Right click on your file or folder.
- Select “Add to archive”. You will see a window “Archive name and parameters”
- Click on the “Set Password” button on the lower right side of the window.
- Fill your desired password, Click OK and then OK again.
- Your file/folder will convert into a RAR file and after the converting process done, you will see 2 folders. One is your original file/folder and the other one is RAR folder. then you can delete your original folder.
- It’s done, now it’s locked and can’t be opened easily, because if somebody try to open it, it will ask for a password and without a correct password nobody can open it (except a big hacker 🙂 ).