Windows provides EFS (Encrypted File System) feature on Windows XP, Windows 2003, Vista and Windows 7 Operating systems. This feature allows users to encrypt their files so that even if anyone gets access to the file he/she will not be able to see the contents. When this feature is enforced on a file, the file will be stored in encrypted form on the disk based on private keys which are unique to each user. When the file owner tries to open the file, the contents will be decrypted using the user key.
To encrypt a file follow the below steps.
- Right click on the folder/file
- Select Properties
- Click on Advanced button
- Then select the check button “Encrypt contents to secure data”
- Click ‘OK‘ and close the windows
- If you are doing it for a folder, you will be asked if you want to do the encryption for subfolders too.
You can see that encrypted files will be shown in green color in explorer window.
On Windows XP, this feature is available only on Professional edition, not in Home edition. Home users will see “Encrypt contents to secure data” grayed out in the advanced attributes window.