Files have disappeared - Boxcrptor drive is empty on all PC's

Symes

Hi - hope someone can help. Have used boxcryptor without problems for a while but have recently ecxperienced a serious problem. The boxcryptor drive suddenly has no files in it - it is the same on all PC's to which I sync. The folder with the encrypted files still has all files in it but, of course, I cannot read them.

I have not forgotten the password or anything. I have tried restoring my pc to an earlier point in time ( when everything was working fine) using an Acronis back up but this has not asolved the problem (I thought maybe the encyption file had become corrupted and this might solve the problem but no joy.) I re-installed boxcryptor but this has had no effect.

If it assists, I have been syncing the files using Windows Live Mesh - worked ok for a few months but suddenly this. Any help would be appreciated...thanks.

Robert

Hi Symes,

when an encrypted file is not shown in the BoxCryptor drive, this might be caused by either a non-matching encryption key or - if filename encryption is enabled - a loss of filename capitalization.

If you have filename encryption enabled and the filename capitalization is lost (e.g. the filename changed from "DjUEu0" to "djueu0") the filename cannot be decrypted anymore and thus the file is not shown. Solutions for this problem are to restore the previous filename or by creating a "dummy" file (create a new empty file with the desired filename, copy the encrypted new filename, delete the dummy file and replace the "broken" filename with the copied one).

The other reason could be the loss of the encryption key. BoxCryptor stores all required information for en-/decryption - secured by your password - in a configuration file named .encfs6.xml which is located in the root of your encrypted folder.

If this file is lost or overwritten, the required key for decryption is lost and decrypting the files is not possible anymore. Overwriting this file can happen if you try to mount an encrypted folder with BoxCryptor on another computer before the whole encrypted folder has been synced completely. If the .encfs6.xml configuration file has not been synced yet, BoxCryptor does not know that this is already an encrypted folder and asks you to create a new password - which is then used to secure a newly generated configuration file.

If this happens, your BoxCryptor drive will appear empty, because the encryption key does not match anymore and the encrypted filenames cannot be decrypted. The only solution for this problem is to restore the original .encfs6.xml configuration file. If this is not possible, the files cannot be decryted anymore.

Most synchronization services like Dropbox allow you to restore previous versions of files, but unfortunately Windows Live Mesh does not seem to offer this feature. Could you restore the .encfs6.xml file from a previous backup you made yourself?

--Robert

Symes

Robert, Thanks for your thoughts. I do not use filename encryption and am guessing your second suggestion is the right one. The only possible way I have of restoring the encryption key is to restore the operating sysytem to an earlier point in time before the problem occurred (using Acronis). However, if I do that then the boxcryptor folder still appears to be empty - presumably this is because it syncs to the encypted folder and the key immediately changes to the 'damaged' key as soon as I launch boxcryptor? (the encrypted folder is stored on a separate partition and is not therefore restored by Acronis.) Is it possible to access the keyfile without actually launching boxctryptor - is it stored somewhere on my C-drive?

Robert

The encryption key is stored in the .encfs6.xml configuration file. This file is stored directly at the root of your encrypted folder. I'm very sorry, but if you don't have a backup of this file it is not possible to restore the encryption key in any way.

klin

Seriously, you guys designed a system where if a file gets lost or corrupt, then you lose all your data?

Luckily for me, I was able to recover the file. Unluckily for you, I'm going to buy PGP now.

Robert

Hi klin,

I'm sorry that you had problems using our product, but good to hear that you could resolve them. In the case of client-side encryption where the key and other encryption information (algorithm, salt, block size, etc.) is only stored on your own devices and not at a central service, it has to be stored locally with the encrypted files. We have published information about the the encryption keys and importance of the configuration file in our Knowledge Base.

Our software is optimized for Dropbox and other cloud storage providers which usually offer file versioning and restoring of deleted files. If your configuration file got deleted or overwritten by accident, it can be restored using those features. If you don't have access to such features, it is always recommended to have a good backup strategy - not only for the BoxCryptor folder.

We're constantly working to improve our products and make them more robust. As posted in the roadmap thread enhancing the key management is an important part of the current development.

--Robert

klin

Thanks for the response. The product should find a way to back up the key which is not related to the file but it sounds like you are going that path. User will panic when they find their files gone and this syncing corruption does not seem like a corner case.

Robert

We are addressing this issue in the next version short-time with an automated prompt to back up the configuration file. Long term we will provide a better key management.

s.lisowski@isti.com

Just FYI in case it helps debug, it seems that when my Windows system experienced a crash (unrelated to dropbox; by plugging in a USB device) on the next boot up, a file I had open at the time of the crash appeared in lowercase in dropbox, and thus missing from boxcryptor folder. I went back to the dropbox history of deleted files, and was able to restore the original upper and lower case name, and get my file back.