Enhancing EFS

Once you have secured your files and assigned user access and recovery agents, you should take steps to aid in data recovery in the event that something happens to your user account. First, you should back up your encryption key and then your user certificate.

Backing Up Your EFS Key

1. Click the Start button and choose Run...
2. Type mmc and click OK.
3. On the File menu, choose Add/Remove Snap-in and then click Add.
4. Under Available Standalone Snap-ins, click Certificates, and then click Add.
5. On the Certificates snap-in dialog, select My user account and then click Finish.
6. Click Close and OK to finish installing the new snap-in.
7. In the left pane of the console window you will see a new heading has been created on the tree display. Click the plus sign next to Certificates - Current User to expand it.
8. Next expand Personal and then expand Certificates.
9. In the right pane, select the entry that says File Recovery in the Intended Use column.
10. Right-click the certificate you just found, point to All Tasks and then click Export to start the Certificate Export Wizard.
11. Click Next.
12. Select Yes, export the private key and click Next.
13. Select Personal Information Exchange - PKCS #12 (.PFX) and also select Enable strong protection, and then click Next to continue.
14. Specify a password. (Note: this is the password that will be required to reinstall you backup. Make sure to pick a strong password that you will remember. I recommend choosing a password that is different from your Windows login password.)
15. Specify a filename and location to save the exported key. I recommend using your Windows user name for the filename and saving it to a removable storage device such as a floppy disk or USB thumb drive. You may also burn the file to a CD.
16. Verify the settings and then click Finish.
17. In the future you will not have to add the Certificates snap-in. Instead you will be able to start at step 7.

Backing Up Your EFS Certificate

1. Start Microsoft Internet Explorer.
2. On the Tools menu, click Internet Options.
3. On the Content tab, in the Certificates section, click Certificates.
4. Click the Personal tab.
5. Select one certificate at a time until the Certificate Intended Purposes field shows Encrypting File System. This is the certificate that was generated when you encrypted your first folder.
6. Click Export to start the Certificate Export Wizard, and then click Next.
7. Click Yes, export the private key to export the private key, and then click Next.
8. Click Enable Strong protection, and then click Next.
9. Type your password. (I recommend not using your Windows password.)
10. Specify the path where you want to save the key. You can save the key to a floppy disk, another location on the hard disk, or a CD. If the hard disk fails or is reformatted, the key and the backup will be lost. (If you back up the key to a floppy disk or CD, you must store that disk or CD in a secure location.)
11. Specify the destination, and then click Next.

Windows 2003 users have the option to backup using a button on the Details page under Advanced Properties when encrypting a file.

Remember to store your encryption key and certificate in a safe place, preferably on removable media.

Finally, you may wish to step up the protection that EFS offers by using the stronger 3DES algorithm. Don't worry about enabling this after encrypting other files. You will still be able to access files that were encrypted with the default DESX algorithm.

Enabling Advanced Encryption By Using 3DES

1. Click the Start button and choose Run...
2. Type gpedit.msc and click OK to start the Group Policy Editor.
3. In the left pane navigate to Computer Configuration > Windows Settings > Security Settings > Local Policies > Security Options.
4. Open the System Cryptography: Use FIPS compliant algorithms for encryption object. (Note that this settings applies to EFS and IPSec).
5. Select enabled and click OK.

Despite its own shortcomings, Encrypted File System still provides a fairly high level of data security. In the digital age, you can't be too safe. It's always a good idea to take advantage of the file protection features that Windows provides. In the event that your system is compromised or stolen, you can have the peace of mind of knowing that your data will be returned intact and unadulterated.

In a future article we will examine the new data protection features being offered in Microsoft Vista. As you will see, Microsoft's dedication to data security is paramount in its latest release.

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