1)   Encrypt PDF (Secure PDF) 2.3
Encrypt PDF software allows you to encrypt (using standard 40-bit or 128-bit supported by Acrobat Reader 5.0 and up) existing PDFs.
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 2)   PDF Security ActiveX 2.0.2008.618
Encrypt and decrypt PDF files Supports PDF user password and owner password protection Password protect opening of the PDF document Disable printing of the PDF document Disable copying of text/graphics
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 3)   Encrypt PDF Command Line 2.3
Encrypt PDF software allows you to encrypt (using standard 40-bit or 128-bit supported by Acrobat Reader 5.0 and up) existing PDFs.
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