Encrypting File System

The Encrypting File System (EFS) on Microsoft Windows is a feature introduced in version 3.0 of NTFS[1] that provides filesystem-level encryption. The technology enables files to be transparently encrypted to protect confidential data from attackers with physical access to the computer.

EFS is available in all versions of Windows except the home versions (see Supported operating systems below) from Windows 2000 onwards.[2] By default, no files are encrypted, but encryption can be enabled by users on a per-file, per-directory, or per-drive basis. Some EFS settings can also be mandated via Group Policy in Windows domain environments.[3]

Cryptographic file system implementations for other operating systems are available, but the Microsoft EFS is not compatible with any of them.[4] See also the list of cryptographic file systems.

  1. ^ "File Encryption (Windows)". Microsoft. Retrieved 2010-01-11.
  2. ^ EFS is available on Windows 2000 Server and Workstation, on Windows XP Professional, on Windows Server 2003 and 2008, and on Windows Vista and Windows 7 Business, Enterprise and Ultimate.
    EFS is not available on Windows XP Home Edition, nor on the Starter, Basic, and Home Premium editions of Windows Vista and Windows 7. It could not be implemented in the Windows 9x series of operating systems, since they did not natively support NTFS, which is the foundation for EFS.
  3. ^ "Encrypting File System". Microsoft. 1 May 2008. Retrieved 24 August 2011.
  4. ^ "Cryptographic Filesystems, Part One: Design and Implementation". Security Focus. Retrieved 2010-01-11.