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Hi,

 

I'm having a hellish problem with EFS. I apologize for the long post

but if anyone can help me, you will truly be doing a kind deed.

 

I have two computers: a laptop running Vista Ultimate and a home server

running 2000 Server.

 

Some time ago, I encrypted some files on my laptop using EFS (I was

concerned the files would be accessible if my laptop was lost or

stolen). I also exported a password-protected encryption key to a

".pfx" file using the certificate export wizard in Vista. I believe,

but I am not absolutely certain, that I included the private key. (My

understanding is that the password is to protect the private key.) I

then emailed this file to a friend for safekeeping.

 

I ran daily mirror backups of these encrypted files up from my Vista

laptop to my Windows 2000 Server at home, using robocopy (not an

incremental backup program). These files remained encrypted when copied

to the server. When I'm physically logged into the server, the files

can be viewed in Windows Explorer, but of course can't be opened,

copied, or otherwise accessed because they were encrypted on another

machine (the Vista laptop). However, I could previously open these

files on my Vista laptop by accessing them over the network, before my

laptop's hard drive failed (see below).

 

A couple of days ago, my laptop's hard drive catastrophically failed.

The failure is mechanical, not just a corrupt boot record or the like.

I say this because I ran the Vista installer to try to repair the drive,

and it did not even recognize that the drive existed. So, my assumption

is that the drive is truly gone.

 

I bought a new hard drive and reinstalled Vista on my laptop. All of

the files that were encrypted using the previous Vista installation are

still on backup drives on my Windows 2000 server, but they are

inaccessible from either the server or the laptop because they are

encrypted.

 

Here's the issue: Recall that I exported a PFX file from my previous

Vista installation and stored it in a safe location. In order to access

the encrypted files, I imported this PFX file using the certificate

import wizard (per MS instructions) into the "Personal" certificate

store, but I still cannot access these files. While importing the file,

I was prompted to give a password, which I correctly gave. From my

understanding, I should now be able to open/decrypt these files, but I

can't. These files are all of my wife's and my critical household

records, so I am desperate to recover them if at all possible.

 

Additional info: While troubleshooting, I downloaded the Elcomsoft

"Advanced EFS Data Recovery" tool. At first, I was able to decrypt a

single small file (an RTF) successfully. I then tried to decrypt some

larger files (Outlook PST and Money MNY files) using the tool. It

appeared to work but the resulting files, though no longer encrypted,

were corrupt and couldn't be opened in their respective applications

without causing errors. As of now, I can no longer get the Elcomsoft

tool to recognize any "decryptable" files-it says they are all

unrecoverable-and so I'm again stuck. But, because I was able to

decrypt a single small file, I have a glimmer of hope that my problem is

procedural and not that I'm missing the encryption key info I need.

 

Also: I tried attaching the server hard drive that contains the

encrypted files directly to my laptop (it's an external USB drive), with

no luck.

 

The main question in my mind is whether my PFX file is somehow lacking

the necessary information to recover my encrypted files, or are my

problems caused by some configuration issue that can be overcome with

more knowledge.

 

Questions:

 

a) Does the prompt to store/enter a password when creating/importing

my pfx file indicate that the private key was stored in the file as well

as the public key? If so, doesn't this mean I should theoretically be

able to decrypt files that were accessible when I created the file?

 

b) Other than just importing the PFX with a wizard and then opening

the file in Windows Explorer, is there some tool or process I could use

to conclusively validate that the PFX file is/isn't capable of

decrypting a given encrypted file?

 

b) Assuming my PFX file has the requisite information, is there some

configuration issue that is preventing me from decrypting these files?

Is the fact that they are stored on a Windows 2000 computer and I am

trying to access them from a Vista computer somehow preventing me from

decrypting them?

 

c) Any other suggestions?

 

Thanks so much for any expertise or advice you can lend. It's my first

foray into this complicated field and I feel like I've done due

diligence by exporting and storing a PFX, but as I say it's not working

and my ignorance has me stuck and frustrated. Does my description ring

any bells about things I might be doing wrong?

 

Cheers, Aaron

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