How to Decrypt Files in Windows XP

The ability to encrypt and decrypt files and folders was introduced in Windows XP and Windows 2000. In order to encrypt files, the Encrypting File System (EFS) is used. Windows XP Professional is the platform on which EFS is utilized. By default, EFS is enabled and available on Windows XP Professional.

Difficulty: Easy

Instructions

Things You'll Need:

• A workstation computer running Windows XP Professional.

Decrypting XP Files

1. 
    
   Log in as jsmith

   Using the "encrypting credentials" (the user name, password of the user who originally encrypted the file), log in to the Windows XP workstation computer where the encrypted file resides. In this example, user "jsmith" is the user who encrypted the file.

2. 
    
   Navigate to encrypted folder

   Browse to the location where the encrypted folder resides. In this example, the encrypted folder is named "safe," and it is under jsmith's "My Documents" folder. Click "Start," then click "My Documents." Your folder containing encrypted data will be unique to your own situation and environment.

3. 
    
   Contents of 'safe' folder

   Double-click the actual encrypted folder(in our example, this is the folder named "safe"). Note that name of the encrypted folder is in a green font, which indicates the folder is encrypted. Note that the names of any encrypted files within the folder also utilize the same green font.

4. 
    
   Open the "Properties" of the encrypted file

   Right-click on the file that needs to be decrypted (in our example, this is the file named "safe1.txt").

5. 
    
   Advanced, under General tab

   Click the "Advanced" button on the "General" tab.

6. 
    
   Decrypt

   To decrypt the file, uncheck the "Encrypt contents to protect data" option, then click "OK" (This option is in the "Advanced Attributes" panel, under the "Compress or Encrypt attributes" section). This will return you to the "General" tab of the "Properties" panel.

7. 
    
   Apply

   Click "Apply" from the "General" tab of the "Properties" panel. You now have decrypted the file.

8. 
    
   Confirm

   Click "Advanced" to confirm that the "Encrypt contents..." check-box is deselected (unchecked). Click "OK;" then, in the "Properties" panel, click "OK" again.

Tips & Warnings

• As an alternative method of decryption, while leaving the original file encrypted, simply open the file, then choose "Save As" and save the file to a folder that is not encrypted. This, in effect, creates a "clear-text, non-encrypted" copy of the original file.
• Always maintain the credentials of the person who originally encrypted the file; otherwise, you will have no means of opening the encrypted file.

Resources

• EFS on XP and Server 2003

[degalasuresh]

on 5/13/2009 Hi, I have a lot of personal files encrypted on my old office laptop. Before I submitted back my laptop I copied those into a hard disk without decrypting them. Now with my new laptop it is not letting me even copy them from the external hard disk. If I create a user with same name, and same password as old one, will I be able to retrieve the personal files? In other words is the encryption purely based on userid and password or it takes into account the desktop details also?