When using the built-in web server, IE9 may hang the server when accessing any web page. This happens frequently; usually on the first or second page although once I was able to successfully access 6 pages in a row. Once the built-in web server is hung, it is hung for all other browsers. The server must either be restarted or all running copies of IE9 must be stopped.
When Chrome is run in Incognito mode, it hangs on the first request. However, accessing the server with any other browser un-freezes the server and both the other browser and the Incognito window are served successfully.
The issue appears to be similar to reported incidents in other single process web servers: