Thanks for that John, I have that option set and still encounter the
error page and the inability to generate new user profiles within ACS
for those subscribing to the test newsletter service.I can get the file
to load for non-logged in users via incognito, but it fails to generated
the new profile and just passes to the error page for the landing page.
The documentations is quite light-on for minimal functionality needed to
achieve, even using the out of the box sample.