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cryptlib 3.0
Security toolkit with strong encryption and authentication. Supports many algorithms for symmetric/asymmetric encryption, authentication, and hashing. Free for non-commercial/shareware projects. Written in C. ActiveX and C++ wrappers are available. 2)
OpenSSL 0.9.7c
Open SSL 0.9.7c lets applications use Secure Sockets Layer (v2/v3), Transport Layer Security (v1), and a general-purpose cryptography library, for data integrity, authenticity, and privacy security features. Perl or Cygwin needed for Win32 compile. 3)
Xceed Encryption Library 1.1
The Xceed Encryption library allows you to easily add strong encryption and decryption capability to your Windows applications. Supports the latest industry-standard strong encryption algorithms and offers both symmetrical and public-key cryptography
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