PDF Secure is a commercial command-line software that empowers users to encrypt, decrypt and re-encrypt multiple PDF files in batch mode. It supports the following encryption algorithms: RC 40-bit, RC 128-bit support and AES.
PDF Secure is a cross-platform application that supports Linux, Unix AIX, Sun Sparc Solaris, Windows, HP-UX, and Mac OS X, in both 32-bit and 64-bit architectures. It does not require Acrobat to run.
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Limitations:
· The software will randomly not process a PDF file and it will display a TRIAL message.