When completing the Portable Document File (PDF) Wizard there is an Encrypt PDF file checkbox in both the Specify PDF file details and Specify email settings screens.
Selecting to encrypt the PDF file
Encrypting enables you to protect the clients privacy by applying a password to the file. Whoever opens an encrypted file must enter a password before they can read it.
For example, when one of your clients receives a PDF of their tax return via email and tries to open it they will be prompted to enter a password. If they do not enter the correct password it will not open.
PDF passwords are case sensitive.
Practice Configuration Settings
The PDF defaults are set: