0
I had a problem on my encrypted files. I tried to uncheck (Encrypt contents to secure data) in the file properties. "An error occurred applying attributes to this file "Access denied." My Deep Freeze program is on during the process of encryption. After my computer restarted, I cannot open the said file. Please help.
Alas
Posted 2014-09-10T11:24:38.367
Reputation: 1
6
I'm guessing that this was the first time you tried to use EFS file encryption on this system, so Windows generated you a fresh keypair; however, when you rebooted, Deep Freeze removed all changes including the new EFS keypair.
By design, if you don't have the encryption key, then you cannot decrypt the data.
The encryption keys are stored in a hidden directory:
C:\Users\<name>\AppData\Roaming\Microsoft\Crypto\RSA\<sid>\
You could try a file recovery tool to see if the keys could be undeleted, although I don't know how to use them directly – you will probably need an EFS recovery tool in addition to that.
My advice: Restore from backups.
user1686
Posted 2014-09-10T11:24:38.367
Reputation: 283 655
Your question is not clear. What did you use to encrypt the files? – Ramhound – 2014-09-10T11:41:09.420
1@Ramhound: "Encrypt contents to secure data" is a setting in the file properties dialog of Windows Explorer, and it activates the built-in EFS encryption. – user1686 – 2014-09-10T11:52:28.980
@grawity - I still feel the author can clarify what he means exactly. I have other questions, like what version of Windows for instance. Helps narrow down the question's scope. – Ramhound – 2014-09-10T13:46:58.100
@Ramhound,@grawity : Thank you for your reply. I do it in Windows 7. Yeah your right it is EFS file encryption and it was my first time to do that. The thing is I encrypt the whole folder while my DEEP FREEZE program is ON, so when my laptop restarted I cannot open the said file. I had just check the encryption keys which is stored in C:\Users<name>\AppData\Roaming\Microsoft\Crypto\RSA<sid>, and i've found 3 keys which was dated yesterday... I think this is not the perfect key. – Alas – 2014-09-11T16:48:23.023
@Alas - What do you mean "its not the perfect key" exactly? – Ramhound – 2014-09-11T16:49:50.260
@Ramhound : Where to find/buy EFS recovery tool? – Alas – 2014-09-11T16:50:08.773
@Ramhound : I cannot restore the system using backup since the last back up I made was when the DEEP FREEZE is OFF... – Alas – 2014-09-11T16:54:10.923
You cannot recover files if they are encrypted. The only solution is to recover the key so you can decrypt the files. If you cannot do that you are out of luck – Ramhound – 2014-09-11T16:54:31.070
@grawity : Do you know any program that solve my problem? The file is very important to me... Thanks for your help... – Alas – 2014-09-11T16:55:47.867
@Ramhound : :( I have 3 encryption keys on my C:, how can I tell that this key is OK.. thanks! How to restore I mean.. – Alas – 2014-09-11T16:58:31.350