I really don't think that function works very well, if at all. The following is a little cumbersome but I have been using it for some time now. 

Create a PDF of the return you want to email.

Save and print the file  as a password protected file with a virtual printer ( I use bullzip)*

Attache the file to your email program.

Inform the recipient of the password.

* Or any conversion program that will password protect and attach to email.

Creating  a shortcut folder of the Proseries PDF files on your desktop, speeds the process along.