If a user is in the detail view for a Case and then scrolls down to the Activities section, there is a button called "Compose Email." When you click the button, it brings up the "Quick Compose" email dialog box. Here's my question...

How can I restrict my users so that the only option in the "From:" pulldown menu (circled in pink in the screenshot attached) is a group email address and NOT the email address of the user?

I can get the "From:" pulldown menu to show BOTH the group and user's email address, but don't know how to restrict it to just the group email address.