The first thing I did after installing Windows 7 RC1 was to toss on my remote apps off of a test server. I have a 2008 Terminal Server that publishes a few common apps for seamless integration. I received a few dissconnects to the remote apps on both windows 7 RC1 boxes that I set up. Here is that message:
RemoteApp Disconnected: Because of a protocol error, this session will be disconnected. Please try connecting to the remote computer again.
It is too soon for me to pin this on the release canidate because I have only spot tested my terminal server set up. But a quick search of the message did not give me many results. As I get more details, I will update this post.