are you sure there weren't any other changes, maybe to your network or something like that? Nothing in 5.0.1 should cause that behavior.
Also can you please try to replace the hostname of your server with its IP address? Sometimes DNS resolving doesn't work for unknown reasons (never had that problem so it's hard to debug) ...
Go to the server list, tap edit, then your server. Delete everything in hostname and replace it with the ip address of your HTPC (if it has a static IP). Now press save.