Hi, All.
OK, complicated network setup...
I have two ADFS servers (Cerberus is the primary, Charon is secondary).
I have an external (non domain) ADFS Proxy server called Styx.
If I point Styx to Cerberus specifically, everything works perfectly. I can go through the proxy config, get trust enabled between the server and the proxy, and my single sign on works like a dream (if a little slow)...
If I point Styx to the NLB (I called it Hercules, for the sake of clarity, since that's the name of my ADFS federated service). I go through the proxy config again (just to make sure everything is working) and it successfully connects to the server, but when I supply the (correct!) domain credentials for authentication, it says that the credentials are wrong.
They aren't, as they were the same ones I used when pointing to the single host.
And yes, I did...