csASPZipFile 

This ASP component creates zip files from files on the server allowing them to be saved or streamed to the browser. It also allows the control of binary file downloads. Includes some file utility functions. Free trial available.
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LockTheFile 

LockTheFile encrypts the content of your important files from hackers and other users. You may protect any information - text files, pictures, video and audio files.
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csFileDownload 

This ASP component enables file downloads to be controlled from within a script. It allows for password protection of individual files, and for record keeping. A built in access code generator is included. There are also some file utility functions.
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