My link to Levy (one of them) got a "Site not Found" on two tries before getting a connection. I got "Site not Found" errors, but that can depend on your machine and browser, and sometimes on what "portals" you go through. Perhaps it's getting heavy traffic?
I'm sure I have a link to Duke, but it would be old, and isn't listed identifiably. (Some of my old links were renamed by content/kind for what I was looking for when I found them.)