An encryption programme for Windows; uses symmetric-key encryption that modifies not only the file, but also the key as it passes though the file. I don't know how good it is, I was just porting an old QBasic programme to Windows because I wanted to learn the Win32 API.

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Programmes I've made myself . . . some of which are of dubious usefulness.

fileobfu.exe (26 KB)

A symmetric-key encryption program whose key is sent to a self-modifying algorithm. By request, updated version 2.0.

fosource.zip (15 KB)

Windows source.

From http://neil.chaosnet.org/software/file-obfuscator/.