From Protect Video Studio:
Password Protect PDF Master is a powerful, easy to use software for pdf document encryption. With Password Protect PDF Master Software, you can encrypt and convert your pdf document to an exe file, create a password to protect your pdf document, It makes your pdf document more secure.
It encrypts the pdf document with the password you specify, and convert the pdf document to an EXE file which can only be opened when a Read Password is provided by you. It supports password PC Binding, on that mode, you only need to encrypt the pdf document one time, and one password can only be used for one computer, to read the password protected pdf document on other computer, it requires another password to open the password protected pdf document.