Encryption for the Masses (E4M) is a free

Free software

Free software, software libre or libre software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with restrictions that only ensure that further recipients can also do...

 disk encryption software for Windows

Microsoft Windows

Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...

 NT/9x/Me. E4M is no longer maintained; its author, Paul Le Roux, joined Shaun Hollingworth (the author of the Scramdisk

Scramdisk

Scramdisk is a free On-the-fly encryption program for Windows 95, Windows 98, and Windows Me. A non-free version was also available for Windows NT....

) to produce E4M's commercial successor, DriveCrypt.

TrueCrypt

TrueCrypt

TrueCrypt is a software application used for on-the-fly encryption . It is free and open source. It can create a virtual encrypted disk within a file or encrypt a partition or the entire storage device .- Operating systems :TrueCrypt supports Microsoft Windows, Mac OS X, and...

 was based on E4M's source code. Truecrypt uses a different container format than E4M, which makes it impossible to use one of these programs to access an encrypted volume created by the other.

See also

• OTFE
  OTFE
  On-the-fly encryption , also known as Real-time Encryption, is a method used by some encryption programs, for example, disk encryption software...
  
  
• Disk encryption
  Disk encryption
  Disk encryption is a special case of data at rest protection when the storage media is a sector-addressable device . This article presents cryptographic aspects of the problem...
  
  
• Disk encryption software
  Disk encryption software
  To protect confidentiality of the data stored on a computer disk a computer security technique called disk encryption is used. This article discusses software that is used to implement the technique...
  
  
• Comparison of disk encryption software
  Comparison of disk encryption software
  -Background information:-Operating systems:-Features:* Hidden containers: Whether hidden containers can be created for deniable encryption...