Your current settings do not allow this program to be downloaded

I'm not sure why, but Norton won't let me download any files.  I am trying to download Firefox, and I receive an error message saying, "Your current settings do not allow this program to be downloaded."

Forgive me if my computer-fu is weak, but I'm not sure how to set Norton to allow me to download files without disabling my protection altogether.  Any help would be greatly appreciated.