Quickly Check Which User Encrypted a File

Daniel Petri

Jan 8, 2009

How can I easily discover who’s the user that encrypted a file?
The Windows Explorer user interface (UI) shows which files are encrypted but not who encrypted them, causing a lot of confusion when trying to access specific files needed by other users. As an administrator, you could rectify the situation by decrypting the files. But wouldn’t you like to know the identity of the dastard that caused the trouble?
The Windows 2000 Resource Kit includes the tool Efsinfo.exe, which you can use to view information about the recovery agent accounts. You can use Efsinfo to verify what recovery accounts are current for an encrypted file.
To determine who the designated recovery agent is after installing the Windows 2000 Resource Kit:

Click Start, point to Programs, point to Accessories, and then click Command Prompt.
Use the cd (change directory) command to change to the folder that contains the encrypted file.
Type efsinfo /r /u filename, where filename is the name of the file you want to check. Or, leave the filename parameter off to report information for all the files in the current folder.

Sample Output from Efsinfo

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EFSINFO /r /u Myfile.doc
Myfile.doc: Encrypted
Users who can decrypt:
DOMAINNAME\Username (CN=User Name,L=EFS,OU=EFS File Encryption Certificate)
Recovery Agents:
DOMAINNAME\EFSRecover (OU=EFS File Encryption Certificate, L=EFS, CN=EFSRecover)

The output indicates that the Myfile.doc file was encrypted by domain user “Username” from domain “Domainname.” The “EFSRecover” account in domain “Domainname” is the designated EFS recovery agent for the file.
For example:

Note: Stand-alone Windows 2000 workstations and servers do not display the recovery agent information. The default recovery agent for all stand-alone computers is the local Administrator account.
You can download Efsinfo from the Download Free Windows 2000 Resource Kit Tools page.