Effect

cipher /e /a <path>

Encrypts all files and subfolders in the specified file system path

cipher /d /a <path>

Decrypts all files and subfolders in the specified file system path

cipher /e /a <path>/*.txt

Encrypts all txt files in the specified file system path.

cipher /e /a /f <path>/*.*

Forces the encryption of all files in the specified file system path. Files that were encrypted previously are re-encrypted.

cipher <path>

Shows the EFS status (Unencrypted or Encrypted) of all files and/or folders in the specified file system path.

cipher /x C:\myefskeys

Backs up a user's EFS key and certificate to a file named mysefskeys