Even if it's local, still make sure it's not a 404

I've found that when I try to get a zip file from the local network, that this section of code is treating all requests as good, even if I get a 404.  I'm not sure of the reasoning behind the isLocal variable, but I think at least making sure the status isn't 404 is a good thing.  Perhaps you could comment on why we can allow something other than 200 for a local request?