I have started getting the 404 Not Found error too. I found that this URL works for me (replace with your S2 IP address):
http://192.168.1.99/index.htmlWow, nice work. How the hell did you figure that out? that's great news.
I don't currently have this problem, but it's probably coming, so it's sure nice to have this solution on deck.
If you figure out an explanation, please do share.