Are you having a problem with RNI or Web page access or both? If Web page then most likely you are using a Web Browser or Web Browser version not supported by the i.LON. See KB930 for supported Web Browsers.
For the RNI, try disabling the firewall temporarily to see if the RNI works to see if it is being blocked by the firewall. You can also change the RNI port on both the LonWorks Interface and i.LON in order to use another port #.