The Cipher command-line utility, which Microsoft built into Windows 2000 (Win2K), displays or alters the encryption of directories and files on NTFS partitions. The Cipher utility supports several commands. Type

cipher /?

to view the switches Table A summarizes.

Used without switches, the Cipher utility displays the encryption state of the current directory and any files it contains. You can use multiple directory names and wildcards. You must type spaces between multiple commands. For example, to encrypt the sales information directory, type

cipher /e "sales information"

To decrypt the directory called "new projects", type

cipher /d new*
Table A: Cipher Switches
Switch Description
/E Encrypts and marks the directories you specify so that EFS will encrypt new files you add.
/D Decrypts and marks the directories you specify so that EFS won’t encrypt new files you add.
/S Performs the operation you specify in a given directory and all its subdirectories.
/A Performs the operation you specify on files and directories.
/I Continues performing the operation you specify even after errors occur. (By default, Cipher stops when it encounters an error.)
/F Forces the encryption operation on the directories you specify, including already-encrypted directories. (By default, Cipher skips already-encrypted directories.)
/Q Reports only the most essential information.
/H Displays file with the hidden (i.e., system) attributes. (By Default, Cipher omits these files from display.)
/K Creates a new file encryption key for you when you run Cipher. When you choose this option, Cipher ignores all other options.
Dirname Specifies a pattern or directory.