Q: How can I disable the Encrypting File System (EFS) to block users from using EFS to encrypt files that are stored on the NTFS file system in Windows 7 or Windows Vista?

A: You can disable EFS using a registry hack. You must modify the value of the NtfsDisableEncryption registry key, which is located in HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlFileSystem. To disable EFS you must set the key to value 1. You can accomplish the same thing by using the following from a command line:

fsutil behavior set disableencryption 1

In both cases, you must restart your computer to apply the change. Remember that EFS is only available in Windows 7 Professional, Ultimate, and Enterprise editions and Windows Vista Business, Ultimate, and Enterprise.