This is embarrassing but .. I installed APEX a few years ago and setup an application to work with the PL/SQL gateway. I haven't touched it in a couple of years but now have a need to do some work on it. But when I try to navigate to the development URL (localhost:8080/pub/pls/myapp), first I get asked for a username and password. I supply the username and password for the database account that was used in the DAD configuration and I can proceed, but I just get a Page Not Found error (even with a simple PL/SQL page that has no possibility of running into issues).
Is there something I need to do to get the instance or workspace to start handling requests? I haven't used APEX in so long I just can't remember.