TrueCrypt is a free open-source disk encryption software for Windows Vista, Windows XP, Mac OS X, and Linux. In essence, it’s a free alternative encryption software which only available for free to Vista Ultimate and Enterprise editions users, as part of Ultimate Extras package. Although TrueCrypt is free, but it’s as powerful is not more powerful that other disk encryption utility available, and comes with more features than disk encryption program for BitLocker.

Main features of TrueCrypt include:

  • Creates a virtual encrypted disk within a file and mounts it as a real disk.
  • Encrypts an entire partition or storage device such as USB flash drive or hard drive.
  • Encrypts a partition or drive where Windows is installed (pre-boot authentication).
  • Encryption is automatic, real-time (on-the-fly) and transparent.
  • Provides two levels of plausible deniability, in case an adversary forces you to reveal the password: hidden volume (steganography) and no TrueCrypt volume can be identified (volumes cannot be distinguished from random data).
  • Encryption algorithms supported including AES-256, Serpent, and Twofish.
  • Mode of operation: XTS.

The TrueCrypt version 5.1 was released on March 10, 2008 has the following new features, enhancements, improvements or bug fixes:

New Features

  • Support for hibernation on computers where the system partition is encrypted in Windows Vista/XP/2008/2003.
  • Ability to mount a partition that is within the key scope of system encryption without pre-boot authentication such as a partition located on the encrypted system drive of another operating system that is not running in Windows Vista/XP/2008/2003. Feature useful for users who want to backup or repair a TrueCrypt encrypted operating system from another operating system.
  • Command line options for creating new volumes in Linux and Mac OS X.


  • Increased speed of AES encryption and decryption in Windows.
  • Faster booting when the system partition is encrypted in Windows Vista/XP/2008/2003.
  • When the system partition/drive is encrypted, the TrueCrypt Boot Loader is now stored in a compressed form and is, therefore, smaller. If a non-cascade encryption algorithm is used (i.e., AES, Serpent, or Twofish), the TrueCrypt Boot Loader is now small enough so that a backup of the TrueCrypt Boot Loader can be (and is) stored in the first drive cylinder. Whenever the TrueCrypt Boot Loader is damaged, its backup copy is run automatically instead.

    As a result of this improvement, the following problem will no longer occur: Certain inappropriately designed activation software (used for activation of some third-party software) writes data to the first drive cylinder, thus damaging the TrueCrypt Boot Loader. The affected users had to use the TrueCrypt Rescue Disk to repair the TrueCrypt Boot Loader. This will no longer be necessary after upgrading to this version of TrueCrypt (provided that the system partition/drive is encrypted using a non-cascade encryption algorithm, i.e., AES, Serpent, or Twofish).

    Note: If your system partition/drive is currently encrypted using a non-cascade encryption algorithm (i.e., AES, Serpent, or Twofish), a backup copy of the TrueCrypt Boot Loader will be automatically stored in the first drive cylinder when you upgrade to this version of TrueCrypt.

  • The minimum memory requirements for the TrueCrypt Boot Loader (AES) have been reduced from 42 KB to 27 KB (twenty-seven kilobytes) in Windows Vista/XP/2008/2003. This allows users to encrypt system partitions/drives on computers where the BIOS reserves a large amount of memory (provided that the AES encryption algorithm is used).

Resolved Incompatibilities

On some computers running Windows Vista/XP/2008/2003, when performing the system encryption pretest, Windows failed to display the log-on screen. This will no longer occur.

Bug Fixes

On some systems, drive letters were not correctly assigned to newly mounted non-system volumes. This will no longer occur. (Windows)

Latest version of TrueCrypt can be downloaded from TrueCrypt download page (see update below). TrueCrypt supports Windows 8, Windows 7, Windows Vista, Windows XP, Windows Server 2000, Windows Server 2003, Windows Server 2008, Mac OS X and OpenSuSE or Ubuntu Linux.

Update: TrueCrypt is not longer supported nor developer since May 2014, and is NOT secure as it may contain unfixed security issues. Users are advised to migrate to BitLocker in Windows, or integrated encryption disks in macOS and Linux. The last available version, TrueCrypt 7.2, is still available on is you’re still interested.