How XP system encrypts offline files
1. Users can select the Folder Options (folders option) command on the Tools menu in Windows Explorer and set the settings for Folder Options in the dialog box that follows to set the encrypted offline file attribute to active.
Description: This option is only available for use in Windows XP Professional.
2. Select the Offline files (offline Files) tab as shown in the following figure.
3. Select Offline files (offline file) tab
4. Also select the Enable Offline files (enable Offline files) and Encrypt Offline files to secure data (encrypting the offline file to secure data) check box.
5. Click OK (OK).
Offline files will be read into the local cache, with the use of private keys and certificates for client computer users to accept encryption.
Note: Do not encrypt a file that has been stored in a roaming user profile, primarily because the file cannot be opened in the configuration once it is loaded during the logon process.