Windows XP has a built in encryption feature so that you can encrypt any file or folder. This feature is only available if your hard disk is NTFS formatted. If you have installed XP on a FAT32 formatted hard disk then you will not be able to use this feature. Most computers that come with Windows XP pre-installed have NTFS formatted hard disks.
Encrypting a file
To encrypt a file in Windows XP, right-click on that file and select Properties. In the Properties dialog, click on the Advanced button. This would open a dialog for Advanced Attributes. Check the checkbox labeled Encrypt contents to secure data and click OK.
After you click OK in the Advanced Attributes dialog to close it, you would see the Apply button would be enabled in the Properties dialog. Click on the Apply button and a warning dialog would be shown. Select the option, Encrypt the file only and click OK. Click OK to close the Properties dialog.
This file can only be opened by the user who encrypted it. Other users on the domain can see the file listed in Windows Explorer but cannot view its contents. The user, who encrypted it, must set options to share access to other users who he/she wants to let view the contents. We will see it later in this article.
Auto encrypting files
You have seen how to encrypt a file in Windows XP. You can follow the same procedure to encrypt a folder. The magical thing about an encrypted folder is that when you copy or move a file or folder inside this encrypted folder, it gets automatically encrypted. So you ca create a secret folder for yourself. If you want some secret files for your eyes only, just move these files into this folder and they would get auto-encrypted.
Color of encrypted files
When a file is encrypted its file name is shown in green color by default in Windows XP. But you can change the options to disable showing the encrypted files/folders in color. For this, open Folder Options from the Control Panel. Select the View tab by clicking on it. In the options list, uncheck the checkbox labeled Show compressed or encrypted NTFS files in color and click OK to save the changes.
Sharing access of encrypted files
By default, the contents of encrypted files are visible only to the user who encrypted the files. But that user can share the access to the contents of the encrypted files to other users of the domain. To do this, right-click on a file, select Properties. In the Properties dialog, click on the Advanced button. This would open a dialog for Advanced Attributes. Click the button labeled Details.
This would open encryption details dialog. In this dialog, click on the button labeled Add and select a user you want to share access with. Once selected, click OK to save the changes.
- Encryption is available only on NTFS formatted hard disks.
- Only the user who encrypted or a system recovery agent (assigned before encryption) can decrypt files.
- All files created in or moved to an encrypted folder get auto-encrypted.
- All encrypted files/folders are shown in green color in Windows XP.