Virtual disk encrypted with DisCryptor, a software utility that securely encrypts important data; similar to a .DCF file, but saved as a virtual disk instead of a standard file archive.

DCO files may be encrypted using Blowfish, Twofish, CAST5, CAST6, MARS, RC5, RC6, Rijndael (AES), or Serpent encryption algorithms. They can be decrypted by an authorized user with DisCryptor Personal or Enterprise software.