In order to encrypt a PDF file, you will need a copy of Adobe Acrobat Professional.
Follow the link below on Adobe's website for instructions on how to perform the encryption.
To encrypt a PDF file, you will need the following:
Please use the following link to find instructions on securing PDFs (Provided by Adobe)
Article ID: 573
Created On: Thu, Dec 8, 2016 at 8:24 AM
Last Updated On: Mon, Mar 19, 2018 at 2:54 PM
Authored by: Trevor Odlum
Online URL: https://knowit.ok.ubc.ca/article/how-do-i-encrypt-a-pdf-file-573.html