Astrotite

Astrotite (and its companion program AstroATP, an online sharing/repairing tool) is an archiver program for the Windows platform which supports some other formats, but has as its native format one with the .afa extension. It supports double-level encryption: one encryption over an entire archive, and another layer of encryption of individual files within the archive, which can even be made invisible from listings of the archive directory unless you use the secret decryption key to extract them.

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 * Info and download