encryption tool

Hi we've recently spent a lot of time and money assembling a group of autolisp codes, toolbars and a custom menu package to aid in the creation of structural steel detail drawings. We would like to make this software available to others in our field, at a price, of course. I was wondering if anyone is aware of an encryption tool and maybe a tool for creating time limited password prompted exe files that we could use for distributing our software on a time limited basis for others to try.

Use the vlisp editor to compile all your code into a VLX file.
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a group of
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in the creation of
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this software
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and maybe a tool
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we could use for
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others to try.
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