Click the save as button and create a custom profile there. There you can also set a password for the file. After you have created a custom profile you can select that one via the profile selection box. Select your profile and click the email button. You custom profile will then be applied and your PDF in the email will be password protected.
I've tried several times to protect a PDF with a password.
I checked the checkbox to protect a PDF with a password; typed the password and then Continue.
The PDF will be stored om my disk and when I double click it will open without asking a password.
Maybe I am doing something wrong, but I've read the instruction several times and I don't know what is going wrong.